воскресенье, 5 июля 2009 г.

Mitochondrial and Y-chromosome diversity of the Tharus (Nepal): a reservoir of genetic variation

Simona Fornarino, Maria Pala, Vincenza Battaglia, Ramona Maranta, Alessandro Achilli, Guido Modiano, Antonio Torroni, Ornella Semino and Silvana A Santachiara-Benerecetti

Background

Central Asia and the Indian subcontinent represent an area considered as a source and a reservoir for human genetic diversity, with many markers taking root here, most of which are the ancestral state of eastern and western haplogroups, while others are local. Between these two regions, Terai (Nepal) is a pivotal passageway allowing, in different times, multiple population interactions, although because of its highly malarial environment, it was scarcely inhabited until a few decades ago, when malaria was eradicated. One of the oldest and the largest indigenous people of Terai is represented by the malaria resistant Tharus, whose gene pool could still retain traces of ancient complex interactions. Until now, however, investigations on their genetic structure have been scarce mainly identifying East Asian signatures.

Results

High-resolution analyses of mitochondrial-DNA (including 34 complete sequences) and Y-chromosome (67 SNPs and 12 STRs) variations carried out in 173 Tharus (two groups from Central and one from Eastern Terai), and 104 Indians (Hindus from Terai and New Delhi and tribals from Andhra Pradesh) allowed the identification of three principal components: East Asian, West Eurasian and Indian, the last including both local and inter-regional sub-components, at least for the Y chromosome.

Conclusions

Although remarkable quantitative and qualitative differences appear among the various population groups and also between sexes within the same group, many mitochondrial-DNA and Y-chromosome lineages are shared or derived from ancient Indian haplogroups, thus revealing a deep shared ancestry between Tharus and Indians. Interestingly, the local Y-chromosome Indian component observed in the Andhra-Pradesh tribals is present in all Tharu groups, whereas the inter-regional component strongly prevails in the two Hindu samples and other Nepalese populations. The complete sequencing of mtDNAs from unresolved haplogroups also provided informative markers that greatly improved the mtDNA phylogeny and allowed the identification of ancient relationships between Tharus and Malaysia, the Andaman Islands and Japan as well as between India and North and East Africa. Overall, this study gives a paradigmatic example of the importance of genetic isolates in revealing variants not easily detectable in the general population.


среда, 10 июня 2009 г.

Eden? Maybe. But Where’s the Apple Tree?

A new genetic survey of people in Africa, the largest of its kind, suggests, however, that the region in southwest Africa seems, on the present evidence, to be the origin of modern humans. The authors have also identified some 14 ancestral populations.

The new data goes far toward equalizing the genetic picture of the world, given that most genetic information has come from European and Asian populations. But because it comes from Africa, the continent on which the human lineage evolved, it also sheds light on the origins of human life.

The origin of a species is generally taken to be the place where its individuals show the greatest genetic diversity. For humans, when the new African data is combined with DNA information from the rest of the world, this spot lies on the coast of southwest Africa near the Kalahari Desert, the research team, led by Sarah A. Tishkoff of the University of Pennsylvania, said in this week’s issue of Science.



The area is a homeland of the Bushmen or San people, whose language is distinguished by its many click sounds.

But the San in the past might not have been restricted to where they are now, she said. The San are thought to have once occupied a much larger area, one that probably stretched from southern Africa up the east coast to as far as present-day Ethiopia.

Since the geneticists’ calculations refer to people, not geography, the San — and therefore the site of greatest human diversity — might have been located elsewhere in the past.

Christopher Ehret, an expert on African languages at the University of California, Los Angeles, and a member of Dr. Tishkoff’s team, has detected traces of words borrowed from click languages in East African languages. This suggests that proto-Khoisan, the inferred ancestral language of all click-speakers, may have originated in East Africa, Dr. Brooks said.

The language of the first modern humans may have undergone a very early branching, Dr. Ehret said, with the Khoisan click languages on one branch and the other three language groups of Africa — Nilo-Saharan, Niger-Kordofanian and Afroasiatic — on the other branch. Clicks are difficult to pronounce fluently and with a single exception no click languages are known outside Africa.

Another finding of the Tishkoff-Ehret team is that African languages tend to be highly correlated with the genetics of their speakers, a finding that helps indicate cases of language replacement. The various Pygmy groups in Africa, the team has found, show distant genetic relationships to the San and other click-speakers, suggesting the pygmies, too, once spoke Khoisan languages but have now adopted those of their neighbors.

Another instance of a mismatch between language and genetics concerns the Luo, an ethnic group in Kenya to which President Obama’s father belonged. The Luo speak a Nilo-Saharan language and are thought of as a people of Sudanese origin, but genetically they have a heavy mixture of Bantu speakers’ genes, Dr. Tishkoff said.

Dr. Tishkoff’s team has also calculated the exit point from which a small human group — maybe a single tribal band of 150 people — left Africa some 50,000 years ago and populated the rest of the world. The region is near the midpoint of the African coast of the Red Sea.

Dr. Tishkoff and her colleagues found that the 14 ancestral African populations they detected are now highly mixed, with the exception of the Bantu speakers.

пятница, 5 июня 2009 г.

Improved Resolution Haplogroup G Phylogeny in the Y Chromosome, Revealed by a Set of Newly Characterized SNPs

Improved Resolution Haplogroup G Phylogeny in the Y Chromosome, Revealed by a Set of Newly Characterized SNPs

Sims et al

Abstract

Background: Y-SNP haplogroup G (hgG), defined by Y-SNP marker M201, is relatively uncommon in the United States general population, with only 8 additional sub-markers characterized. Many of the previously described eight sub-markers are either very rare (2–4%) or do not distinguish between major populations within this hg. In fact, prior to the current study, only 2% of our reference Caucasian population belonged to hgG and all of these individuals were in sub-haplogroup G2a, defined by P15. Additional Y-SNPs are needed in order to differentiate between individuals within this haplogroup. Principal Findings: In this work we have investigated whether we could differentiate between a population of 63 hgG individuals using previously uncharacterized Y-SNPs. We have designed assays to test these individuals using all known hgG SNPs (n = 9) and an additional 16 unreported/undefined Y-SNPS. Using a combination of DNA sequence and genetic genealogy databases, we have uncovered a total of 15 new hgG SNPs that had been previously reported but not phylogenetically characterized. Ten of the new Y-SNPs are phylogenetically equivalent to M201, one is equivalent to P15 and, interestingly, four create new, separate haplogroups. Three of the latter are more common than many of the previously defined Y-SNPs. Y-STR data from these individuals show that DYS385*12 is present in (70%) of G2a3b1-U13 individuals while only 4% of non-G2a3b1-U13 individuals posses the DYS385*12 allele.




вторник, 2 июня 2009 г.

Баварские дДНК

Kinship and Y-Chromosome Analysis of 7th Century Human Remains: Novel DNA Extraction and Typing Procedure for Ancient Material // Croat Med J. 2009 Jun;50(3):286-95

Vanek et al

http://www.cmj.hr/2009/50/3/19480023.htm

4/6 R1b1b2
2/6 G2a

Сделаны гаплотипы по 26 локусам (не полные).

Sample YSEARCH identifier

244A/244B 6QUDR
244C H78RA
244D ZYRUU
244E* H6KZ2, QCX3T
244F 2SRMA


The grave 244 makes this place one of the richest Bavarian burial sites from the late-Merowig period. The grave 244 dates to the period around 670 AD.







воскресенье, 24 мая 2009 г.

Найдено недостающее звено в цепи эволюции человека

Ученые на специальной пресс-конференции в Нью-Йорке рассказали об обнаружении «потерянного» звена эволюции человека — ископаемого скелета обезьяны возрастом 47 млн лет.

Находку рассматривают как свидетельство прямой связи между людьми и остальным царством животных.

Ученые уже назвали «лемура-обезьяну» (она получила имя Ида) восьмым чудом света.

Как сообщает Day.Az со ссылкой на Newsland, существование этого промежуточного между людьми и другими млекопитающими вида окончательно подтвердило теорию эволюции Чарльза Дарвина.

Напомним, что исследователи австралийского Центра по изучению геномики кенгуру пришли к необычному выводу, что 150 млн лет назад у человека и кенгуру был общий предок. «Все, что мы сделали, это составили детализированную карту генома кенгуру. Она напоминает карту улицы, на которой находятся 20 тысяч домов», — сообщил директор центра Дженни Грэйвз.

Расшифровав геном, ученые смогли сравнить ДНК сумчатых и человека. «Мы думали, что там будет все наизнанку, но оказалось совсем не так. В геноме кенгуру находятся большие куски человеческого генома», — отметил профессор.

Ученые называют свое исследование историческим, полагая, что его результаты помогут точнее представить, как проходила эволюция человека. По их мнению, общий предок человека и кенгуру жил 150 млн лет назад, в то время как мыши и люди «отделились» друг от друга всего 70 млн лет назад.

Найдены генетические мутации, отвечающие за «синдром оборотня»

Ученые определили, какие генетические мутации приводят к «синдрому оборотня».

Это проявляется у людей в результате очень редкого наследственного заболевания, при котором практически все тело человека покрывается обильным волосяным покровом.

Как сообщает Day.Az со ссылкой на Newsland, этим редким заболеванием страдают как женщины, так и мужчины. Большую известность оно получило в 19 веке после цирковых выступлений артистки Юлии Пастраны, демонстрировавшей в ходе представления бороду на своем лице, а так же волосы на руках и ногах.

Иногда это заболевание называют «синдромом оборотня», так как страдающие им люди обладают не только очень густым волосяным покровом, но и широким плоским носом, большими ушами и ртом, толстыми губами, а иногда и увеличенной челюстью.

Изучить причины, вызывающие столь серьезное заболевание, практически гарантированно передающееся по наследству, не удавалось до последнего времени, так как случаи его проявления очень редки. Авторы публикации под руководством Сюе Чзана из Объединенного пекинского медицинского колледжа потратили 4 года на поиски среди миллиардной китайской популяции людей, страдающих «синдромом оборотня».

В результат такой подготовительной работы ученым удалось найти всего три китайских семьи, 16 членов которых больны общим гипертрихозом. Ученые исследовали ДНК больных и сравнили их с ДНК 19 здоровых членов семей. Оказалось, что вредную мутацию несет на себе 17 хромосома, а сама мутация у всех 16 подопечных представляет собой отсутствие длинного фрагмента ДНК, несущего на себе дополнительные копии генов.

По мнению Чзана, мутация приводит к реорганизации хромосомы, которая затрагивает процессы считывания генов, соседствующих с «вырезанным» участком. Так одним из соседей этих генов является ген SOX9, отвечающий за рост волос. По всей видимости, реорганизация хромосомы приводит к тому, что считывание этого гена многократно усиливается, приводя к перепроизводству белков, способствующих росту волос.

«Это пока умозрительные заключения, и роль мутации нам еще предстоит доказать», - сказал Чзан.

Как появилась жизнь на Земле

14 мая, 16:55 | Владимир СТРЕЛЬЦОВ

Эксперимент английских ученых устранил основные противоречия в теории возникновения жизни на Земле, базирующейся на произвольном синтезе молекул РНК. Джону Сазерленду и его коллегам из Манчестерского университета в Великобритании удалось синтезировать рибонуклеотид - строительный "кирпичик" молекулы РНК - из простейших химических элементов в условиях, сходных с теми, что были на ранней стадии развития нашей планеты.

Результат эксперимента буквально "обновил" гипотезу происхождения жизни из РНК. Согласно ей, молекула рибонуклеиновой кислоты, соотносимой с ДНК, которая может воспроизводить сама себя и вступать в необходимые реакции, появилась в "пребиотическом супе" - смеси органических и неорганических веществ, наполнявшей первобытный океан. Она и стала первоосновой всего живого на Земле.

Однако, как она могла возникнуть в природе сама по себе, ученые не понимали до сих пор. Молекула РНК - длинная цепочечная частица, состоящая из единичных звеньев - нуклеотидов. Каждый из них, в свою очередь, представляет собой три части - азотистое основание, углевод рибозы и остаток фосфорной кислоты.

Долгое время исследователи полагали, что эти составные части нуклеотидов сформировались по отдельности и впоследствии объединялись в длинные молекулы. Но однажды образованные по отдельности азотистые основания и рибоза в природных условиях взаимодействовать с образованием нуклеотидов не могут, что до сих пор и ставило ученых в тупик. Основной помехой для синтеза в условиях "пребиотического супа" является присутствие множества посторонних элементов.

Сазерленд и его коллеги смогли построить процесс синтеза, на определенной стадии которого получилось вещество 2-амнооксазол. Это соединение отличается большой летучестью, а потому ученые полагают, что в условиях "пребиотического супа" оно могло быть выделено и очищено от примесей возгонкой. Днем при солнечном освещении и нагревании это соединение испарялось, а ночью при охлаждении оседало обратно в концентрированной форме, которую можно назвать "органическим снегом". После этого превращение аминооксазола в нуклеотид, содержащий рибозу с присоединенным к ней азотистым основанием, проходит всего в нескольких стадий.

Ученые обнаружили ген старения

Ученые продвинулись на один шаг вперед на пути к открытию секрета вечной молодости и долголетия.

Как сообщает Day.Az со ссылкой на Health-ua.org,тайваньские исследователи утверждают, что им удалось найти ген, связанный со старением.

И, хотя на данный момент эксперименты проводились на мышах, потенциально это открытие может привести к увеличению срока человеческой жизни, считают они.

Исследователи из Национального университета Янг-Минг в Тайбэе, Тайвань, случайно наткнулись на ген Cisd2 во время работы, в ходе которой они пытались найти гены, связанные с развитием рака печени у мышей, сообщает газета Taipei Times. В результате, они наблюдали преждевременный процесс старения у мыши в возрасте 8 недель, у которой удалили этот ген. У мыши поседела шерсть, она потеряла вес, а также мышечную и костную массу.

Исследование проводилось командой из 12 ученых под руководством профессора Тсай Тинг-Фен, которая заведует генетической лабораторией мышей при университетском институте генных наук. Мышь, которой удалили ген Cisd2, жила примерно год – это в два раза меньше среднего срока жизни мышей. Тсай рассказала, что она и её команда продолжают работать над тем, как заставить этот ген работать лучше с помощью диеты, богатой антиоксидантами.

Ученые настаивают на том, что положительное влияние на работу гена оказывает диета, полная антиоксидантов. «Вы никогда не ошибетесь, если включите в свой рацион овощи и фрукты, и будете есть их в больших количествах», - сказала она, прежде чем рассказать о планах на будущее.

суббота, 16 мая 2009 г.

The first European: Created from fragments of fossil, the face of our forbears 35,000 years ago

Dressed in a suit, this person would not look out of place in a busy street in a modern city.

The clay sculpture, however, portrays the face of the earliest known modern European - a man or woman who hunted deer and gathered fruit and herbs in ancient forests more than 35,000 years ago.

It was created by Richard Neave, one of Britain's leading forensic scientists, using fossilised fragments of skull and jawbone found in a cave seven years ago.

Forensic Scientist Richard Neave reconstructed the face based on skull fragments from 35,000 years ago

The first modern European: Forensic artist Richard Neave reconstructed the face based on skull fragments from 35,000 years ago

His recreation offers a tantalising glimpse into life before the dawn of civilisation. It also shows the close links between the first European settlers and their immediate African ancestors.

To sculpt the head, Mr Neave called on his years of experience recreating the appearance of murder victims as well as using careful measurements of bone.

It was made for the BBC2 series The Incredible Human Journey. This will follow the evolution of humans from the cradle of Africa to the waves of migrations that saw Homo sapiens colonise the globe.

The head has taken pride of place on the desk of Alice Roberts, an anthropologist at Bristol University, who presents the programme.

'It's really quite bizarre,' she told Radio Times. 'I'm a scientist and objective but I look at that face and think "Gosh, I'm looking at the face of somebody from 40,000 years ago" and there's something weirdly moving about that.

'Richard creates skulls of much more recent humans and he's used to looking at differences between populations.

'He said the skull doesn't look European or Asian or African. It looks like a mixture of all of them.

'That's probably what you'd expect of someone among the earliest populations to come to Europe.'

Anthropologist Alice Roberts with the model

Anthropologist Alice Roberts with the model: 'I look at that face and think "I'm actually looking at the face of somebody from 40,000 years ago"', she says

The head is based on remains of one of the earliest known anatomically modern Europeans.

The lower jawbone was discovered by potholers in the Carpathian mountains in Romania in 2002. The rest of the fragments were found the following year.

The bones were carbon-dated to between 34,000 and 36,000 years ago when Europe was occupied by two species of human.

They were the Neanderthals, who had arrived from Africa tens of thousands of years earlier, and the more recent modern humans, also known as Cro-Magnons.

Although the skull is similar to a modern human head, it has a larger cranium, is more robust and has larger molars. Although it is impossible to work out the skin colour of the prehistoric hunter, it is likely to have been darker than modern white Europeans.

Fossil experts are also unsure if the skull was male or female.

Many scientists believe that modern humans evolved in Africa 200,000 to 100,000 years ago. Our ancestors left Africa around 60,000 years ago and migrated around the world, replacing other branches of the family tree which had left the continent earlier.

The earliest modern Europeans were far from primitive. Living in huts and caves, they used stone tools and spears made from antlers, painted on the walls of their caves and made jewellery from shells.

четверг, 14 мая 2009 г.

Y chromosome haplogroup R1a is associated with prostate cancer risk among Macedonian males

Y chromosome haplogroup R1a is associated with prostate cancer risk among Macedonian males

D. Plaseska-Karanfilska et al.

Prostate cancer (PC) is one of the most common male-specific cancers. Its incidence varies considerably between populations. Recent surveys suggest that PC is influenced by both genetic and environmental factors, although the etiology of the disease remains unknown in the majority of cases. Certain Y chromosomal lineages have been suggested to predispose individuals to prostate cancer in Japanese population, but no association has been found among Korean and Swedish patients. The aim of this study was to investigate the association between Y chromosomal haplogroups and predisposition to prostate cancer in Macedonian men. We studied 84 PC patients and 126 males from the general population of Macedonian ethnic origin. A total of 28 markers have been studied by multiplex PCR and SNaPshot analysis. Nineteen different Y haplogroups were determined; the most frequent being I1b-P37b, E3b1-M78, R1a-SRY 1532, R1b-P25 and J2b1a-M241. The frequency of R1a was significantly higher in PC patients (20.2%) in comparison with the controls (9.5%) [p=0.027; OR=2.41 (1.09-5.36)]. When stratified according to age, even stronger association was observed between haplogroup R1a and prostate cancer in patients of >65 years of age [p=0.004; OR=3.24 (1.41-7.46)]. Our results suggest that Y chromosome haplogroup R1a is associated with an increased prostate cancer risk in Macedonian men.

Pigment phenotype and biogeographical ancestry from ancient skeletal remains: inferences from multiplexed autosomal SNP analysis

Pigment phenotype and biogeographical ancestry from ancient skeletal remains: inferences from multiplexed autosomal SNP analysis

Caroline Bouakaze Contact Information, Christine Keyser Eric Crubézy, Daniel Montagnon and Bertrand Ludes

Abstract In the present study, a multiplexed genotyping assay for ten single nucleotide polymorphisms (SNPs) located within six pigmentation candidate genes was developed on modern biological samples and applied to DNA retrieved from 25 archeological human remains from southern central Siberia dating from the Bronze and Iron Ages. SNP genotyping was successful for the majority of ancient samples and revealed that most probably had typical European pigment features, i.e., blue or green eye color, light hair color and skin type, and were likely of European individual ancestry. To our knowledge, this study reports for the first time the multiplexed typing of autosomal SNPs on aged and degraded DNA. By providing valuable information on pigment traits of an individual and allowing individual biogeographical ancestry estimation, autosomal SNP typing can improve ancient DNA studies and aid human identification in some forensic casework situations when used to complement conventional molecular markers.

Association of Y chromosome haplogroup I with HIV progression, and HAART outcome

Association of Y chromosome haplogroup I with HIV progression, and HAART outcome

Efe Sezgin, Joanne M. Lind, Sadeep Shrestha, Sher Hendrickson, James J. Goedert, Sharyne Donfield, Gregory D. Kirk, John P. Phair, Jennifer L. Troyer, Stephen J. O’Brien and Michael W. Smith

Abstract
The host genetic basis of differential outcomes in HIV infection, progression, viral load set point and highly active retroviral therapy (HAART) responses was examined for the common Y haplogroups in European Americans and African Americans. Accelerated progression to acquired immune deficiency syndrome (AIDS) and related death in European Americans among Y chromosome haplogroup I (Y-I) subjects was discovered. Additionally, Y-I haplogroup subjects on HAART took a longer time to HIV-1 viral suppression and were more likely to fail HAART. Both the accelerated progression and longer time to viral suppression results observed in haplogroup Y-I were significant after false-discovery-rate corrections. A higher frequency of AIDS-defining illnesses was also observed in haplogroup Y-I. These effects were independent of the previously identified autosomal AIDS restriction genes. When the Y-I haplogroup subjects were further subdivided into six I subhaplogroups, no one subhaplogroup accounted for the effects on HIV progression, viral load or HAART response. Adjustment of the analyses for population stratification found significant and concordant haplogroup Y-I results. The Y chromosome haplogroup analyses of HIV infection and progression in African Americans were not significant. Our results suggest that one or more loci on the Y chromosome found on haplogroup Y-I have an effect on AIDS progression and treatment responses in European Americans.

A female figurine from the basal Aurignacian of Hohle Fels Cave in southwestern Germany

A female figurine from the basal Aurignacian of Hohle Fels Cave in southwestern Germany

Nicholas J. Conard


Despite well over 100 years of research and debate, the origins of art remain contentious1, 2, 3. In recent years, abstract depictions have been documented at southern African sites dating to approx75 kyr before present (bp)4, 5, and the earliest figurative art, which is often seen as an important proxy for advanced symbolic communication, has been documented in Europe as dating to between 30 and 40 kyr bp 2. Here I report the discovery of a female mammoth-ivory figurine in the basal Aurignacian deposit at Hohle Fels Cave in the Swabian Jura of southwestern Germany during excavations in 2008. This figurine was produced at least 35,000 calendar years ago, making it one of the oldest known examples of figurative art. This discovery predates the well-known Venuses from the Gravettian culture by at least 5,000 years and radically changes our views of the context and meaning of the earliest Palaeolithic art.

Изучена старейшая убитая семья

Изучена старейшая убитая семья

Четыре лежащие неподалёку друг от друга могилы 4600-летнего возраста археологи обнаружили близ немецкого города Эйлау (Eulau) ещё в 2005 году. Но только теперь Вольфганг Хаак (Wolfgang Haak) из Австралийского центра изучения древней ДНК (Australian centre for ancient DNA) и его коллеги из Германии и Великобритании выполнили мультидисциплинарный анализ находки, рассказавший интересные детали о данном захоронении.

Всего в нём находились восемь детей в возрасте от шести месяцев до девяти лет и пять взрослых в возрасте от 25 до 60. Состояние останков (по меньшей мере у пятерых — переломанные кости и пробитые черепа) говорило о том, что эти люди погибли в результате нападения врагов на поселение. У одного из несчастных в позвонке даже застрял наконечник каменного оружия.

У "обитателей" двух могил из четырёх неплохо сохранились ДНК. Это позволило установить, что в первой находилась целая семья — отец, мать и двое детей (интересно, что сын и дочь похоронены на руках своих родителей). Данное исследование, таким образом, это древнейшее на данный момент молекулярно-генетическое свидетельство нуклеарной семьи (одна брачная пара с детьми, ещё не состоящими в браке и находящимися на иждивении родителей), — пишут авторы работы. А это признак перехода к современному обществу.

Во второй могиле находились трое детей, генетически родственных, и не связанная с ними женщина, возможно, тётя или мачеха.


Все 13 человек представляют собой группу, принадлежащую к так называемой Культуре шнуровой керамики (Corded Ware Culture), распространённой в Европе с позднего неолита до раннего бронзового века. Для неё как раз были характерны захоронения с расположением взрослых на боку лицом на юг, а детей — в руках родителей, лицом к ним (как и в изученных могилах). Так древние европейцы обозначали родственные связи покойных.

Помимо генетического авторы работы выполнили и геохимический анализ, изучив содержание изотопов стронция в зубах погребённых. Эти изотопы откладываются в детстве, попадая в организм с пищей. Последняя же (растения, например) получает их из местных почв. Таким способом можно установить место рождения человека, поскольку распределение изотопов в каждом районе — своё.

Оказалось, что у всех детей и взрослых мужчин в зубах имелся "одинаковый" стронций, но у женщин картина была иная. Ближайшее совпадение по стронцию имелось в 50 километрах от этого места.

По словам учёных, это свидетельствует об уже распространившейся в то время экзогамии: женщин отдавали замуж в другую общину. Важная цель такой практики — укрепление отношений между соседями, обеспечение поддержки на случай войны или неурожая.

О войне нужно сказать отдельно. Поскольку большинство людей в этих захоронениях — женщины и дети, как поясняет Хаак, есть вероятность, что большинство взрослых обитателей поселения находились в момент нападения в другом месте, возможно, участвовали в вооружённой стычке или работали на полях.

"Они вернулись домой в деревню и нашли своих родных и близких погибшими. Это только предположение, но наиболее правдоподобное объяснение", — утверждает Вольфганг.

Такое насилие вписывается в то, что антропологам и историкам известно о Центральной Европе того времени. Плодородные почвы и стабильный климат делали её желанным местом для жизни, но это же создавало конкуренцию, приводившую к конфронтации.

суббота, 17 января 2009 г.

Was Megalithic Culture Earth's First Empire?

Advocates of lost civilization theories, including the likes of Graham Hancock (author of Fingerprints of the Gods) and earlier, Charles Hapgood (Maps of the Ancient Sea Kings) have proposed the existence of a world-spanning homogeneous maritime civilization whose apex occurred as much as 12,000 years before our current technological high-water mark. Very often, these writers are careful to avoid mention of the word ‘Atlantis’, but the main belief structure behind all these theories remains fundamentally the same: more than 10,000 years ago, before our recorded history, there existed a relatively advanced civilization that attained a high enough level of culture that they had written languages, maritime trade and sophisticated naval technology.

Leaving aside – for the moment – such superficial, facile approaches as comparison and contrast of New World and Old World pyramids…in fact, steering away from all the Von Danikenesque hyperbole, is there any evidence for a civilization anything like what we’ve described above?

As it happens, there is.

European Megalithic Culture was a prehistoric culture that stretched from the Iberian Peninsula in the south and Sweden and the Orkney Islands in the north, while stretching from the Baltics in the east as far west as the Atlantic.

The earliest structures in this civilization can be reliably dated to about 4800 BC, and consist of circular ditches and communal tombs, and later evolved to include more complicated structures, including henges (the most famous of which is Stonehenge in Somerset, England).

The people belonging to this megalithic culture displayed highly advanced technologies at an almost incredibly early date. For example, by 4000 BC, the Neolithic inhabitants of the Orkneys, Hebrides and Shetlands were demonstrably using skin boats and voyaging nearly out of sight of land. Skara Brae, the spectacular megalithic culture settlement uncovered in the Orkneys features extremely well-designed houses and hearths, some of which seem to include provision for a not-so-primitive sort of plumbing. In England, the first evidence of farming became evident, along with stone axes and distinctive grooved pottery. The culture was knitted together in its use of a common measurement system, most particularly in the use of the megalithic yard, discovered in 1955 by Prof. Alexander Thom, professor of Engineering Sciences at Oxford University. In his March 23 submission to the Journal of the Royal Statistical Society, Vol. 118, Thom described the results of more than 20 years of research, at 250 megalithic sites in England and Scotland. Above all, Thom reported that he isolated a common unit of measure, constituting exactly 2.72 feet, and present in site after site.

Many – if not the majority -- of the henges and standing stones erected by the Megalithic Culture displayed astronomical alignments with solstices, equinoxes and the movements of the sun, moon and stars. Some, such as Newgrange or Maes Howe would be masterpieces today, even without the incredible intricacies of their alignments. Add in their sophisticated astronomical capabilities – Maes Howe is aligned to the setting winter solstice sun and to the winter setting full Venus, while Newgrange is aligned to the rising winter solstice sun and the winter rising full venus – and you have artifacts of unparalleled sophistication for their time.

Additionally, says Robert Lomas, author of Uriel’s Machine and Mysteries of the Ancient World, they possessed centralized manufacturing and mass production techniques. He cites axes as evidence, illustrating how ax heads were created at two specific sites (with a sea voyage separating them), then finished, polished and fitted with shafts at two other sites. The wide-ranging nature of their trade supply chain is established by the fact that these mass-produced axes are found throughout Britain. Just from this one example, says Lomas, we can infer that the Megalithic Culture people specialized into roles which – for the purposes of ax production – included quarry workers, sailors, polishers and finishers, and “a sales force”.

At around the same time – as much as two thousand years prior to the pyramids – a predynastic Egyptian people began building their own megalithic structures on the Nabta plateau near the Sudanese border. These structures would seem to mark the position where the morning star, Sirius, would have risen at the spring solstice.

Academics such Grafton Elliot Smith, an Australian anatomist who was a proponent of the theory of hyperdiffusionism, which suggested that all megalith-builders originated from Egypt, believed the Nabta peoples and the European Megalithic Culture peoples were one and the same. Today, the hyperdiffusionist theory has fallen out of favour, but there remains the coincidental emergence of cultures within a few hundred years, both of which erect standing stones to track astronomical phenomena.

There also remain the startling similarities between Mediterranean Megalithic structures and those in northern and western Europe, with structures in Sardinia, Sicily and Malta being almost identical. Both cultures featured henges, chambered tombs and standing stones.

So who, then, were the Megalithic Culture peoples? One theory, known as the Anatolian hypothesis, popularized by Colin Renfrew, suggests that they were a Proto-Indo-European (PIE) people from Anatolia, who migrated into Europe along with the spread of Neolithic agriculture. More recent thinking about the spread of the PIE-speaking peoples has tended to reject this, largely on the grounds that the Proto-Indo-Europeans expanded out of the Pontic Steppe later, in the 4th millennium. This theory, called the Kurgan hypothesis, suggests that this migration occurred too late to account for the Megalithic Culture.

Others propose that the migration may have taken place the other way. At around 10,000 BC, the Azilian-Tardenoisian peoples – considered to be the first wave of the Iberians – migrated into Europe. There are suggestions that – unlike other theories which suggest an east-to-west populating of Europe – the Azilian-Tardenoisians arrived from the Atlantic. Their provenance as a sea-going people is further supported by finds of finely worked, but very large, fish-hooks. In this theory, the Megalithic Culture is simply the result of 5000+ years of evolution from a landfall made on the Iberian peninsula at the closing of the Ice Age.

Barry Cunliffe, professor of European Architecture at Oxford University, has pointed out the relative homogeneity of the Megalithic Culture – or at least that of the European Megalithic Culture. Writing in an article titled People of the Sea, in the February 2002 issue of British Archaeology, he says in the late bronze age “had a warrior from the Algarve sailed to Aberdeenshire he would have found much in local behaviour and equipment that was very familiar.”

Cunliffe goes on to say, “it is quite clear...that the technical skills of the people, both in shipbuilding and navigation, must have been sufficiently advanced, even at a very early date, to allow voyages in the open sea to have been a normal part of life...if we accept that networks of maritime communication along the entire Atlantic façade had developed during the Mesolithic period, then it is easier to understand how the cultural traits of agro-pastoralism, which characterized the subsequent Neolithic way of life, quickly spread from the Mediterranean to the Atlantic coast of Portugal and from Continental Europe to the British Isles and Ireland.”

One of the most recent weapons added to the arsenal of those studying the relatively mute passages of prehistory is biostatistics and the analysis of genetic information, particularly Y-DNA. Much groundbreaking study has been done by researchers such as S. Rootsi and Luigi Luca Cavalli-Sforza. One of the more revealing findings to emerge from the new discipline of “genetic geography” may be the identification of a Megalithic Culture genetic ‘fingerprint’, Y-DNA haplogroup I.

According to the International Society of Genetic Genealogy, “Y-DNA haplogroup I is a European haplogroup, representing nearly one-fifth of the population. It is almost non-existent outside of Europe, suggesting that it arose in Europe. Estimates of the age of haplogroup I suggest that it arose prior to the last Glacial Maximum. Probably, it was confined to the refuge in the Balkans during the last Ice Age, and then spread northward during the recolonization of northern Europe following the retreat of the glaciers.
There are two main subgroups of haplogroup I: I-M253/I-M307/I-P30/I-P40 has highest frequency in Scandinavia, Iceland, and northwest Europe. In Britain, haplogroup I-M253 is often used as a marker for "invaders," Viking or Anglo-Saxon. I-S31 includes I-P37.2, which is the most common form in the Balkans and Sardinia, and I-S23/I-S30/I-S32/I-S33, which reaches its highest frequency along the northwest coast of continental Europe. Within I-S23 et al, I-M223 occurs in Britain and northwest continental Europe. A subgroup of I-M223, namely I-M284, occurs almost exclusively in Britain, so it apparently originated there and has probably been present for thousands of years.”

What this seems to suggest is that not only is a pan-European common megalithic ethinic culture not far-fetched, but even quite likely, based on the Y-DNA evidence. In fact, given the significant presence of Haplogroup I in Sardinia, which spread along the northwest coast of continental Europe – often considered the “heartland” of megalithic culture we may even be able to infer links to the Mediterranean megalithic culture.

If this is true – and only further research will tell one way or another – the implications are manifold. For one thing, later Bronze Age migrations (not to mention predations) of the Sea Peoples (which were thought to contain a significant Sardinian and Corsican continent), demonstrated the relative ease with which a population in this portion of the Mediterranean to easily influence culture in the Aegean, Crete, Malta, the Phoenician / Lebanese Coast and even as far south as Egypt. Given this, perhaps hyperdiffusionist theory needs to be considered once again.

This would mean that the megaliths of Malta, Brittany, southern England, the Orkney Islands, Crete, Lebanon (Baalbek) and even Nabta on the Egypt/Sudan border really are far-flung outposts of a common cultural empire.

And if that can be established, how likely is it that other megalithic cultures – for example those in China, India and Japan – that existed at roughly the same time, and built similar structures, are completely unrelated? Or does Occam’s razor suggest that there may be a relationship; indeed, perhaps just another branch of a global, world-spanning homogeneous civilization, spread through maritime travel, whose apex occurred as much as 12,000 years before our current technological high-water mark.

среда, 7 января 2009 г.

Скорость развития СПИДа зависит от ДНК митохондрий

Скорость, с которой ВИЧ-инфекция переходит в СПИД, определяется носительством того или иного вариант а ДНК митохондрий. Некоторые варианты митохондриальной ДНК (так называемые гапло группы) ассоциируются с ускорением развития СПИДа в два раза, сообщает журнал New Scientist.

Стивен О'Брайан (Stephen O'Brien) и его коллеги из Национального института рака в Фредерике (штат Мэриленд, США) изучили данные пяти долгосрочных

исследований с участием 1833 ВИЧ-инфицированных пациентов. Все исследования были проведены в 80-х и начале 90-х годов прошлого века, до широкого внедрения антиретровирусной терапии, что позволило проследить естественный ход развития заболевания.

В ходе экспериментов ученые определяли продолжительность течения ВИЧ-инфекции у пациентов до развития СПИД-ассоциированных заболеваний. Эти данные сопоставлялись с их вариантом ДНК митохондрий – клеточных структур, занимающихся выработкой энергии. Митохондриальная ДНК, передающаяся только по материнской линии, позволяет определить географическое происхождение семейной группы. В зависимости от вариаций митохондриальной ДНК выделяют так называемые гаплогруппы, которые показывают, к какой генеалогической ветви человечества относится той или иной человек.

Выяснилось, что у людей, принадлежащих к митохондриальной гаплогруппам U5a1 и J, ВИЧ-инфекция прогрессировала в два раза быстрее, чем в среднем у участников. В тоже время у тех, кто принадлежал к гаплогруппе H3, СПИД развивался более чем в два раза дольше, показало исследование.

Ученые отметили, что митохондриальные гаплогруппы различаются по количеству вырабатываемой ими энергии, причем гаплогруппы U5a1 и J вырабатывают меньшее количество энергии. Провоцируемый ВИЧ апоптоз (клеточная гибель) активнее протекает в тех иммунных клетках, митохондрии которых вырабатывают меньше энергии. Этот факт может служить возможным объяснением ускоренного развития СПИДа у пациентов, принадлежащих к гаплогруппам U5a1 и J.

В будущем определение митохондриальной ДНК может быть использовано при прогнозировании развития ВИЧ у пациента, а также для определения сроков начала антиретровирусной терапии, резюмировали ученые.