| Human Genetics | |
|---|---|
| Tweet Topic Started: Feb 29 2016, 06:38 AM (2,775 Views) | |
| ThirdTerm | Feb 29 2016, 06:38 AM Post #1 |
|
Administrator
|
Berit Myhre Dupuy, Margurethe Stenersen, Tim T. Lu, and Bjørnar Olaisen. "Geographical heterogeneity of Y-chromosomal lineages in Norway." Forensic Science International 164:1 (December 1, 2006): pages 10-19. First published online on December 7, 2005. The Y-DNA of 1766 unrelated Norwegian males was studied. The team found 726 different lineages, grouped into 7 haplogroups: P*(xR1a), BR(xDE, J, N3, P), R1a, N3, DE, J, and "one previously undescribed haplogroup (probably a subgroup within haplogroup P*(xR1a))." The haplogroups DE and J were found in minute frequencies, only 2% combined. The breakdown of the 4 top haplogroups was: I1 = 37.3% R1b = 31.3% R1a = 26.3% N3 = 3.8% Haplogroup N3 was found at an elevated 11% of Norwegians from northern Norway (especially Finnmark where 18.6% of the Norwegians have it) whereas none of the Norwegians in southern Norway had it. Scientists believe N3 came to Norwegians through intermarriage with Saami and Finnish men, as based on data from all populations N3 "has been interpreted as a signature of Uralic Finno-Ugric speaking males migrating to northern Scandinavia about 4000-5000 years ago". |
![]() |
|
| ThirdTerm | Mar 1 2016, 09:24 PM Post #2 |
|
Administrator
|
Haplogroup N9a is characteristic of eastern Asian populations, where it is detected at a highest frequencies in Japan (4.6%), China (2.8%), Mongolia (2.1%) and Korea (3.9%) [8], [21], [32], [34]. Haplogroup N9a is rare in Taiwan (1.2%) and Island southeastern Asia (1.1%) [22], [30], but appears at greater frequencies in Mainland southeastern Asia (1.5–4.5%) [24], [33]. With the comparable frequencies this haplogroup is detected in several populations of northern (0.9%–4.6%) and central Asia (1.2–2.5%), but it is virtually absent in western and southern Asia [8], [32], [35], [36]. Interestingly, haplogroup N9a is rarely found in the Volga-Ural region Tatars (∼1%) and Bashkirs (1.5%) as well as in some eastern Europeans, like Russians from southwestern Russia (1.5%) and Czechs (0.6%) [37]–[40]. http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0032179 I got a few more details about N9a3 from email correspondence with William Boyce, who wrote about Ashkenazim having N9a3 here, and previously here and here (those two pages are now offline and not archived). Boyce told me: "[...] the n9a3 haplogroup found in about 1-2% of Ashkenazim [...] it is very rare, and found only sparsely, in regions stretching from Siberia to Kazackstan, Mongolia to South China. [...] Inside of the DIY 23andMe community, I've so far tracked down a dozen Ashkenazim (almost all with maternal Lithuanian roots), as well as 4 individuals of East Asian descent (2 South Korean, 1 Chinese, 1 Japanese), and one non-Ashkenazi European of maternal Romanian descent. N9a3 seems to have no more than a 2 to 3% presence in any given population, but is spread throughout a wide geographical area (including to my knowledge, Buryat, Siberian, Korean, Japanese, Chinese, Uzbek, Mongol and Altaic/Turkic peoples). I've also seen various data suggesting N9a3 is found in Hungarian, Czech and Southern Russian populations, but at incidence of no more than 1%." Later, in March 2015, Boyce observed: "I continue to find is that upwards of 90% percent of N9a3's through 23andme outside Ashkenazi's are of Korean descent." Boyce told me in March 2015 that he heard from a Turkish Jewish woman who belongs to N9a3 and says her maternal grandmother's mother came from the North Caucusus (presumably a Mountain Jew?). He was building a population map that shows Ashkenazic carriers of N9a3 whose ancestors lived in Lithuania (including Vištytis), Belarus (including Slutsk), Ukraine, and Russia. There's an N9a3 carrier in Qingdao, China of Chinese ethnicity. Lulu Q. Lin's family is from Shanghai, China "in recent generations" and she belongs to N9a3 as she commented on August 29, 2014 at 9:24pm. A staff member of the DNA laboratory Táiwān Jīyīn Sùyuán (Taiwan Gene Traceability) commented on August 2, 2015 at 5:14pm: "We also have someone tested N9a3. In Taiwan, 1.5% people have N9a3." http://www.khazaria.com/genetics/aj-east-asian-admixture.html Edited by ThirdTerm, Mar 1 2016, 09:30 PM.
|
![]() |
|
| ThirdTerm | Mar 3 2016, 11:12 PM Post #3 |
|
Administrator
|
![]() At the top are shown drawings illustrating the seven hair features examined in the CANDELA study sample. Thick lines connect these features with the candidate genes identified in regions with SNPs reaching genome-wide significant association (Table 1). At the bottom is shown a composite Manhattan plot displaying all significantly associated SNPs for the hair features examined. The rs number of the SNP with the smallest P value is shown at the top of each association peak (Table 1 index SNP). Composite panels in this and subsequent figures were made using Photoshop67. |
![]() |
|
| ThirdTerm | Mar 4 2016, 04:50 AM Post #4 |
|
Administrator
|
![]() Approximately 60% of Nuristanis carry Y-DNA Haplogroup R1a (Haber et. al 2012). Haplogroup L3a (PK3) is found at high levels – approximately 23% – of Nuristani males.[29] L3a is also found found frequently among Burusho (approximately 12%) and Pashtuns (approx. 7%), and is distributed at a moderate level throughout the general population of Pakistan (at a rate of approx. 2%).[29] Its highest frequency can be found in south western Balochistan province along the Makran coast (28%) to Indus River delta. |
![]() |
|
| ThirdTerm | Mar 4 2016, 04:54 AM Post #5 |
|
Administrator
|
![]() Genetic analysis of Y-chromosome DNA (Y-DNA) by Firasat et al. (2007) on Kalash individuals found high and diverse frequencies of these Y-DNA Haplogroups: L3a (22.7%), H1* (20.5%), R1a (18.2%), G (18.2%), J2 (9.1%), R* (6.8%), R1* (2.3%), and L* (2.3%).[36] Genetic analysis of Mitochondrial DNA (mtDNA) by Quintana-Murci et al. (2004) stated that "the western Eurasian presence in the Kalash population reaches a frequency of 100%" with the most prevalent mtDNA Haplogroups being U4 (34%), R0 (23%), U2e (16%), and J2 (9%). The study asserted that no East or South Asian lineages were detected and that the Kalash population is composed of western Eurasian lineages (as the associated lineages are rare or absent in the surrounding populations). The authors concluded that a western Eurasian origin for the Kalash is likely, in view of their maternal lineages.[37] |
![]() |
|
| ThirdTerm | Mar 4 2016, 07:15 PM Post #6 |
|
Administrator
|
![]() A new study from Harvard University, 23andMe, and Olay has suggested a possible explanation that has to do with genes rather than expensive skin care. A team of scientists led by Harvard professor of dermatology Alexa Kimball analyzed data from 231 women* across two ethnic groups (provided by 23andMe) and found that Methuselah genes, or “younger genes" — the ones responsible for characteristics like more-effective DNA repair and the skin's ability to protect against damaging environmental factors (sunlight, etc.) — are found in one-fifth of black Americans, while only one in ten white Americans is a carrier. The presence of these genes allows some people to look ten years younger than their age, according to the paper. http://www.bostonmagazine.com/health/blog/2015/06/10/mde-study-harvard/ The study also discovered exactly how a woman’s skin ages by decade: decline in antioxidant response (20s); decline in skin bioenergy (30s); increase in cellular senescence (40s); decline in skin barrier function (50s); acceleration of all the above (60s). The initial findings of this MDE study include data from Caucasian and African research participants. Olay reps say that they are continuing to collect and analyze samples from Asian and Hispanic women in their 20s through 70s to broaden how they can use the study’s findings to create new products to help fight skin aging. “Once completed, the MDE study will have examined female skin aging throughout six distinct decades and across four different ethnicities,” reps say. http://www.bostonmagazine.com/health/blog/2015/06/10/mde-study-harvard/ |
![]() |
|
| ThirdTerm | Mar 4 2016, 08:20 PM Post #7 |
|
Administrator
|
In Malaysia, the Malays consist of several sub-groups, e.g., Melayu Minang, Melayu Jawa, Melayu Bugis and Melayu Kelantan, based on their respective geographical origins. Malay sub-groups have various historical origins and genetic affinities1,2. Both ancient and recent human activities have introduced gene flows from other populations into the Malays3,4,5. The indigenous groups (Orang Asli) in Malaysia, including Proto-Malay, Senoi and Negrito, interacted with the Malays because their habitats were situated adjacent to one another. The Malays are genetically related to the Orang Asli despite differences in their physical features5. For example, Negritos have short stature and very dark skin, which are more similar to the phenotypes of African Pygmies than to those of other Southeast Asian populations6,7. In addition, populations from other regions of Asia, even from other continents, have cultural and genetic influences on the Malays to various extents. In particular, Chinese, Indians, Arabians, and Europeans have substantially influenced the region since ancient times, and have had a more considerable impact in recent centuries due to the colonization and globalization of the entire human society, thus leading to the mosaic genomic pattern in the Malays2,5,8. Besides Malaysia, the Malays are distributed in the surrounding islands, e.g. Peninsular Indo-China, Singapore, Java, and Sri Lanka9. Malay populations share a common origin with other Austronesian populations9. During the 1400s and 1500s, the Malacca Sultanate was established and subsequently dominated the entire Malay Archipelago, and the Malay language was established as the official language in that region, replacing Sanskrit. The Malays, especially those in the western and southern Malaysia, have had frequent interactions with other Austronesian populations through trading or other social activities10. These early contacts did not result in a large-scale of population admixture, but intermarriage did exist. Gradually, the Malays mixed with the local residents in the surrounding islands, and have developed into various Malay ethnic groups2. These Malay ethnic groups affect not only the demography but also the culture, including religions and languages, outside Malaysia. However, the Malay people have been largely under-represented in studies on human genetic diversity and are not on the population list of large-scale international projects, such as the the International Haplotype Map Project11 (HapMap, http://www.hapmap.org), the Human Genome Diversity Project12 (HGDP, http://www.hagsc.org/hgdp) and the 1000 Genomes Project13 (http://www.1000genomes.org). Some recent studies on Asian populations have included a few Malay samples from Malaysia, Indonesia and Singapore8,14,15, but other Malay populations residing outside of Southeast Asia such as those living in Sri Lanka, have not been well studied. http://www.nature.com/articles/srep14375 |
![]() |
|
| ThirdTerm | Mar 5 2016, 04:39 AM Post #8 |
|
Administrator
|
![]() Haplogroup R1a1-M198 is a major clade of Y chromosomal haplogroups which is distributed all across Eurasia. To this date, many efforts have been made to identify large SNP-based subgroups and migration patterns of this haplogroup. The origin and spread of R1a1 chromosomes in Eurasia has, however, remained unknown due to the lack of downstream SNPs within the R1a1 haplogroup. Since the discovery of R1a1-M458, this is the first scientific attempt to divide haplogroup R1a1-M198 into multiple SNP-based sub-haplogroups. We have genotyped 217 R1a1-M198 samples from seven different population groups at M458, as well as the Z280 and Z93 SNPs recently identified from the “1000 Genomes Project”. The two additional binary markers present an effective tool because now more than 98% of the samples analyzed assign to one of the three sub-haplogroups. R1a1-M458 and R1a1-Z280 were typical for the Hungarian population groups, whereas R1a1-Z93 was typical for Malaysian Indians and the Hungarian Roma. Inner and Central Asia is an overlap zone for the R1a1-Z280 and R1a1-Z93 lineages. This pattern implies that an early differentiation zone of R1a1-M198 conceivably occurred somewhere within the Eurasian Steppes or the Middle East and Caucasus region as they lie between South Asia and Eastern Europe. The detection of the Z93 paternal genetic imprint in the Hungarian Roma gene pool is consistent with South Asian ancestry and amends the view that H1a-M82 is their only discernible paternal lineage of Indian heritage. http://blogs.discovermagazine.com/gnxp/2012/10/r1a1a/#.Vtpgtfl97IU |
![]() |
|
| ThirdTerm | Mar 5 2016, 05:32 AM Post #9 |
|
Administrator
|
Historic Japanese culture evolved from at least two distinct migrations that originated on the Asian continent. Hunter-gatherers arrived before land bridges were submerged after the last glacial maximum (>12,000 years ago) and gave rise to the Jomon culture, and the Yayoi migration brought wet rice agriculture from Korea beginning approx2,300 years ago. A set of 81 Y chromosome single nucleotide polymorphisms (SNPs) was used to trace the origins of Paleolithic and Neolithic components of the Japanese paternal gene pool, and to determine the relative contribution of Jomon and Yayoi Y chromosome lineages to modern Japanese. Our global sample consisted of >2,500 males from 39 Asian populations, including six populations sampled from across the Japanese archipelago. Japanese populations were characterized by the presence of two major (D and O) and two minor (C and N) clades of Y chromosomes, each with several sub-lineages. Haplogroup D chromosomes were present at 34.7% and were distributed in a U-shaped pattern with the highest frequency in the northern Ainu and southern Ryukyuans. In contrast, haplogroup O lineages (51.8%) were distributed in an inverted U-shaped pattern with a maximum frequency on Kyushu. Coalescent analyses of Y chromosome short tandem repeat diversity indicated that haplogroups D and C began their expansions in Japan approx20,000 and approx12,000 years ago, respectively, while haplogroup O-47z began its expansion only approx4,000 years ago. We infer that these patterns result from separate and distinct genetic contributions from both the Jomon and the Yayoi cultures to modern Japanese, with varying levels of admixture between these two populations across the archipelago. The results also support the hypothesis of a Central Asian origin of Jomonese ancestors, and a Southeast Asian origin of the ancestors of the Yayoi, contra previous models based on morphological and genetic evidence. https://www.researchgate.net/publication/7441547_Dual_origins_of_the_Japanese_Common_ground_for_hunter-gatherer_and_farmer_Y_chromosomes |
![]() |
|
| ThirdTerm | Mar 5 2016, 07:34 AM Post #10 |
|
Administrator
|
How modern humans dispersed into Eurasia and Australasia, including the number of separate expansions and their timings, is highly debated [ 1, 2 ]. Two categories of models are proposed for the dispersal of non-Africans: (1) single dispersal, i.e., a single major diffusion of modern humans across Eurasia and Australasia [ 3–5 ]; and (2) multiple dispersal, i.e., additional earlier population expansions that may have contributed to the genetic diversity of some present-day humans outside of Africa [ 6–9 ]. Many variants of these models focus largely on Asia and Australasia, neglecting human dispersal into Europe, thus explaining only a subset of the entire colonization process outside of Africa [ 3–5, 8, 9 ]. The genetic diversity of the first modern humans who spread into Europe during the Late Pleistocene and the impact of subsequent climatic events on their demography are largely unknown. Here we analyze 55 complete human mitochondrial genomes (mtDNAs) of hunter-gatherers spanning ∼35,000 years of European prehistory. We unexpectedly find mtDNA lineage M in individuals prior to the Last Glacial Maximum (LGM). This lineage is absent in contemporary Europeans, although it is found at high frequency in modern Asians, Australasians, and Native Americans. Dating the most recent common ancestor of each of the modern non-African mtDNA clades reveals their single, late, and rapid dispersal less than 55,000 years ago. Demographic modeling not only indicates an LGM genetic bottleneck, but also provides surprising evidence of a major population turnover in Europe around 14,500 years ago during the Late Glacial, a period of climatic instability at the end of the Pleistocene. http://www.cell.com/current-biology/abstract/S0960-9822(16)00087-7 Some older Cro-Magnons belonged to Haplogroup C6 and it's no surprise to discover the mtDNA lineage M in European hunter-gatherers, who may still have been part Asian at the time. In Europe, C-M130* has also been found in males with the surname Llach in Spain and it was also identified in "Kostenki 14", an ancient Siberian dating from 34,000 years BP. The study examined human fossils between 35,000 and 7,000 years old from Spain to Russia, where you could find more Asiatic human specimens. Edited by ThirdTerm, Mar 5 2016, 07:59 AM.
|
![]() |
|
| 1 user reading this topic (1 Guest and 0 Anonymous) | |
| Go to Next Page | |
| « Previous Topic · General Discussion · Next Topic » |
| Theme: Zeta Original | Track Topic · E-mail Topic |
7:04 PM Jul 11
|













7:04 PM Jul 11