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1.
BMC Biol ; 17(1): 3, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30674303

RESUMO

BACKGROUND: Recent genome studies of modern and ancient samples have proposed that Native Americans derive from a subset of the Eurasian gene pool carried to America by an ancestral Beringian population, from which two well-differentiated components originated and subsequently mixed in different proportion during their spread in the Americas. To assess the timing, places of origin and extent of admixture between these components, we performed an analysis of the Y-chromosome haplogroup Q, which is the only Pan-American haplogroup and accounts for virtually all Native American Y chromosomes in Mesoamerica and South America. RESULTS: Our analyses of 1.5 Mb of 152 Y chromosomes, 34 re-sequenced in this work, support a "coastal and inland routes scenario" for the first entrance of modern humans in North America. We show a major phase of male population growth in the Americas after 15 thousand years ago (kya), followed by a period of constant population size from 8 to 3 kya, after which a secondary sign of growth was registered. The estimated dates of the first expansion in Mesoamerica and the Isthmo-Colombian Area, mainly revealed by haplogroup Q-Z780, suggest an entrance in South America prior to 15 kya. During the global constant population size phase, local South American hints of growth were registered by different Q-M848 sub-clades. These expansion events, which started during the Holocene with the improvement of climatic conditions, can be ascribed to multiple cultural changes rather than a steady population growth and a single cohesive culture diffusion as it occurred in Europe. CONCLUSIONS: We established and dated a detailed haplogroup Q phylogeny that provides new insights into the geographic distribution of its Eurasian and American branches in modern and ancient samples.


Assuntos
Cromossomos Humanos Y , Variação Genética , Haplótipos , Indígenas Norte-Americanos/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética , América , Europa (Continente) , Genética Populacional , Humanos , Filogenia
2.
Proc Natl Acad Sci U S A ; 110(35): 14308-13, 2013 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23940335

RESUMO

In this study we evaluated migration models to the Americas by using the information contained in native mitochondrial genomes (mitogenomes) from North America. Molecular and phylogeographic analyses of B2a mitogenomes, which are absent in Eskimo-Aleut and northern Na-Dene speakers, revealed that this haplogroup arose in North America ∼11-13 ka from one of the founder Paleo-Indian B2 mitogenomes. In contrast, haplogroup A2a, which is typical of Eskimo-Aleuts and Na-Dene, but also present in the easternmost Siberian groups, originated only 4-7 ka in Alaska, led to the first Paleo-Eskimo settlement of northern Canada and Greenland, and contributed to the formation of the Na-Dene gene pool. However, mitogenomes also show that Amerindians from northern North America, without any distinction between Na-Dene and non-Na-Dene, were heavily affected by an additional and distinctive Beringian genetic input. In conclusion, most mtDNA variation (along the double-continent) stems from the first wave from Beringia, which followed the Pacific coastal route. This was accompanied or followed by a second inland migratory event, marked by haplogroups X2a and C4c, which affected all Amerindian groups of Northern North America. Much later, the ancestral A2a carriers spread from Alaska, undertaking both a westward migration to Asia and an eastward expansion into the circumpolar regions of Canada. Thus, the first American founders left the greatest genetic mark but the original maternal makeup of North American Natives was subsequently reshaped by additional streams of gene flow and local population dynamics, making a three-wave view too simplistic.


Assuntos
Emigração e Imigração , Migração Humana , Indígenas Norte-Americanos/genética , Genoma Humano , Humanos
3.
Am J Hum Genet ; 90(5): 915-24, 2012 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-22560092

RESUMO

Human populations, along with those of many other species, are thought to have contracted into a number of refuge areas at the height of the last Ice Age. European populations are believed to be, to a large extent, the descendants of the inhabitants of these refugia, and some extant mtDNA lineages can be traced to refugia in Franco-Cantabria (haplogroups H1, H3, V, and U5b1), the Italian Peninsula (U5b3), and the East European Plain (U4 and U5a). Parts of the Near East, such as the Levant, were also continuously inhabited throughout the Last Glacial Maximum, but unlike western and eastern Europe, no archaeological or genetic evidence for Late Glacial expansions into Europe from the Near East has hitherto been discovered. Here we report, on the basis of an enlarged whole-genome mitochondrial database, that a substantial, perhaps predominant, signal from mitochondrial haplogroups J and T, previously thought to have spread primarily from the Near East into Europe with the Neolithic population, may in fact reflect dispersals during the Late Glacial period, ∼19-12 thousand years (ka) ago.


Assuntos
DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Mitocôndrias/genética , População Branca/genética , Europa (Continente) , Europa Oriental/epidemiologia , Variação Genética , Genética Populacional , Humanos , Oriente Médio , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA
4.
Genome Res ; 22(5): 821-6, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22454235

RESUMO

Mitochondrial DNA (mtDNA) lineages of macro-haplogroup L (excluding the derived L3 branches M and N) represent the majority of the typical sub-Saharan mtDNA variability. In Europe, these mtDNAs account for <1% of the total but, when analyzed at the level of control region, they show no signals of having evolved within the European continent, an observation that is compatible with a recent arrival from the African continent. To further evaluate this issue, we analyzed 69 mitochondrial genomes belonging to various L sublineages from a wide range of European populations. Phylogeographic analyses showed that ~65% of the European L lineages most likely arrived in rather recent historical times, including the Romanization period, the Arab conquest of the Iberian Peninsula and Sicily, and during the period of the Atlantic slave trade. However, the remaining 35% of L mtDNAs form European-specific subclades, revealing that there was gene flow from sub-Saharan Africa toward Europe as early as 11,000 yr ago.


Assuntos
DNA Mitocondrial/genética , África/etnologia , Emigração e Imigração/história , Europa (Continente) , Evolução Molecular , Haplótipos , História Antiga , Humanos , Dados de Sequência Molecular , Filogenia , Filogeografia , Análise de Componente Principal
5.
Genome Res ; 22(5): 811-20, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22333566

RESUMO

It is now widely agreed that the Native American founders originated from a Beringian source population ~15-18 thousand years ago (kya) and rapidly populated all of the New World, probably mainly following the Pacific coastal route. However, details about the migration into the Americas and the routes pursued on the continent still remain unresolved, despite numerous genetic, archaeological, and linguistic investigations. To examine the pioneering peopling phase of the South American continent, we screened literature and mtDNA databases and identified two novel mitochondrial DNA (mtDNA) clades, here named D1g and D1j, within the pan-American haplogroup D1. They both show overall rare occurrences but local high frequencies, and are essentially restricted to populations from the Southern Cone of South America (Chile and Argentina). We selected and completely sequenced 43 D1g and D1j mtDNA genomes applying highest quality standards. Molecular and phylogeographic analyses revealed extensive variation within each of the two clades and possibly distinct dispersal patterns. Their age estimates agree with the dating of the earliest archaeological sites in South America and indicate that the Paleo-Indian spread along the entire longitude of the American double continent might have taken even <2000 yr. This study confirms that major sampling and sequencing efforts are mandatory for uncovering all of the most basal variation in the Native American mtDNA haplogroups and for clarification of Paleo-Indian migrations, by targeting, if possible, both the general mixed population of national states and autochthonous Native American groups, especially in South America.


Assuntos
Emigração e Imigração/história , Genoma Mitocondrial , Indígenas Sul-Americanos/genética , Frequência do Gene , Haplótipos , História Antiga , Humanos , Indígenas Sul-Americanos/história , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , América do Sul
6.
Proc Natl Acad Sci U S A ; 109(7): 2449-54, 2012 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-22308342

RESUMO

Archaeological and genetic evidence concerning the time and mode of wild horse (Equus ferus) domestication is still debated. High levels of genetic diversity in horse mtDNA have been detected when analyzing the control region; recurrent mutations, however, tend to blur the structure of the phylogenetic tree. Here, we brought the horse mtDNA phylogeny to the highest level of molecular resolution by analyzing 83 mitochondrial genomes from modern horses across Asia, Europe, the Middle East, and the Americas. Our data reveal 18 major haplogroups (A-R) with radiation times that are mostly confined to the Neolithic and later periods and place the root of the phylogeny corresponding to the Ancestral Mare Mitogenome at ~130-160 thousand years ago. All haplogroups were detected in modern horses from Asia, but F was only found in E. przewalskii--the only remaining wild horse. Therefore, a wide range of matrilineal lineages from the extinct E. ferus underwent domestication in the Eurasian steppes during the Eneolithic period and were transmitted to modern E. caballus breeds. Importantly, now that the major horse haplogroups have been defined, each with diagnostic mutational motifs (in both the coding and control regions), these haplotypes could be easily used to (i) classify well-preserved ancient remains, (ii) (re)assess the haplogroup variation of modern breeds, including Thoroughbreds, and (iii) evaluate the possible role of mtDNA backgrounds in racehorse performance.


Assuntos
Animais Domésticos/genética , DNA Mitocondrial/genética , Genoma , Haplótipos , Cavalos/genética , Animais , Cavalos/classificação , Filogenia
7.
Genome Res ; 21(5): 768-74, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21324875

RESUMO

Accurate estimation of recent shared ancestry is important for genetics, evolution, medicine, conservation biology, and forensics. Established methods estimate kinship accurately for first-degree through third-degree relatives. We demonstrate that chromosomal segments shared by two individuals due to identity by descent (IBD) provide much additional information about shared ancestry. We developed a maximum-likelihood method for the estimation of recent shared ancestry (ERSA) from the number and lengths of IBD segments derived from high-density SNP or whole-genome sequence data. We used ERSA to estimate relationships from SNP genotypes in 169 individuals from three large, well-defined human pedigrees. ERSA is accurate to within one degree of relationship for 97% of first-degree through fifth-degree relatives and 80% of sixth-degree and seventh-degree relatives. We demonstrate that ERSA's statistical power approaches the maximum theoretical limit imposed by the fact that distant relatives frequently share no DNA through a common ancestor. ERSA greatly expands the range of relationships that can be estimated from genetic data and is implemented in a freely available software package.


Assuntos
Padrões de Herança/genética , Funções Verossimilhança , Modelos Genéticos , Modelos Estatísticos , Linhagem , Mapeamento Cromossômico , DNA/genética , Família , Ligação Genética , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Polimorfismo de Nucleotídeo Único , Análise de Componente Principal , Software
8.
Genome Res ; 20(9): 1174-9, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20587512

RESUMO

Pan-American mitochondrial DNA (mtDNA) haplogroup C1 has been recently subdivided into three branches, two of which (C1b and C1c) are characterized by ages and geographical distributions that are indicative of an early arrival from Beringia with Paleo-Indians. In contrast, the estimated ages of C1d--the third subset of C1--looked too young to fit the above scenario. To define the origin of this enigmatic C1 branch, we completely sequenced 63 C1d mitochondrial genomes from a wide range of geographically diverse, mixed, and indigenous American populations. The revised phylogeny not only brings the age of C1d within the range of that of its two sister clades, but reveals that there were two C1d founder genomes for Paleo-Indians. Thus, the recognized maternal founding lineages of Native Americans are at least 15, indicating that the overall number of Beringian or Asian founder mitochondrial genomes will probably increase extensively when all Native American haplogroups reach the same level of phylogenetic and genomic resolution as obtained here for C1d.


Assuntos
Genoma Mitocondrial/genética , Indígenas Norte-Americanos/genética , América , DNA Mitocondrial/genética , Emigração e Imigração , Variação Genética , Genoma Humano , Geografia , Haplótipos , Humanos , Dados de Sequência Molecular , Filogenia
9.
Int J Legal Med ; 127(1): 77-83, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22395921

RESUMO

It has been recorded that one of the possible causes that eventually escalated into the 1857 manslaughter at Mountain Meadows in Southern Utah was the poisoning of an open spring by the Fancher-Baker party as they crossed the Utah territory on their way from Arkansas to California. Historical accounts report that a number of cattle died, followed by human casualties from those that came in contact with the dead animals. Even after the Arkansas party departed, animals continued to perish and people were still afflicted by some unknown plague. Proctor Hancock Robison, a local 14-year-old boy, died shortly after skinning one of the "poisoned" cows. A careful review of the historical records, along with the more recent scientific literature, seems to exclude the likelihood of actual poisoning in favor of a more recent theory that would point to the bacterium Bacillus anthracis as the possible cause of human and animal deaths. In order to test this hypothesis, Proctor's remains were exhumed, identified through mitochondrial DNA analysis, and tested for the presence of anthrax spores. Although preliminary testing of remains and soil was negative, description of the clinical conditions that affected Proctor and other individuals does not completely rule out the hypothesis of death by anthrax.


Assuntos
Antraz/história , Bacillus anthracis/genética , DNA Mitocondrial/genética , Animais , Antraz/genética , Osso e Ossos/química , Bovinos/microbiologia , DNA Bacteriano/genética , Exumação , Feminino , História do Século XIX , Humanos , Masculino , RNA Ribossômico 16S , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia do Solo , Esporos Bacterianos , Utah
10.
Am J Hum Genet ; 84(6): 814-21, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19500771

RESUMO

There are extensive data indicating that some glacial refuge zones of southern Europe (Franco-Cantabria, Balkans, and Ukraine) were major genetic sources for the human recolonization of the continent at the beginning of the Holocene. Intriguingly, there is no genetic evidence that the refuge area located in the Italian Peninsula contributed to this process. Here we show, through phylogeographic analyses of mitochondrial DNA (mtDNA) variation performed at the highest level of molecular resolution (52 entire mitochondrial genomes), that the most likely homeland for U5b3-a haplogroup present at a very low frequency across Europe-was the Italian Peninsula. In contrast to mtDNA haplogroups that expanded from other refugia, the Holocene expansion of haplogroup U5b3 toward the North was restricted by the Alps and occurred only along the Mediterranean coasts, mainly toward nearby Provence (southern France). From there, approximately 7,000-9,000 years ago, a subclade of this haplogroup moved to Sardinia, possibly as a result of the obsidian trade that linked the two regions, leaving a distinctive signature in the modern people of the island. This scenario strikingly matches the age, distribution, and postulated geographic source of a Sardinian Y chromosome haplogroup (I2a2-M26), a paradigmatic case in the European context of a founder event marking both female and male lineages.


Assuntos
Cromossomos Humanos Y/genética , DNA Mitocondrial/genética , Genética Populacional , Haplótipos/genética , Paleopatologia , Evolução Molecular , Feminino , Humanos , Itália , Masculino , Dados de Sequência Molecular , Linhagem
11.
BMC Genet ; 13: 39, 2012 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-22606979

RESUMO

BACKGROUND: Populations of the Americas were founded by early migrants from Asia, and some have experienced recent genetic admixture. To better characterize the native and non-native ancestry components in populations from the Americas, we analyzed 815,377 autosomal SNPs, mitochondrial hypervariable segments I and II, and 36 Y-chromosome STRs from 24 Mesoamerican Totonacs and 23 South American Bolivians. RESULTS AND CONCLUSIONS: We analyzed common genomic regions from native Bolivian and Totonac populations to identify 324 highly predictive Native American ancestry informative markers (AIMs). As few as 40-50 of these AIMs perform nearly as well as large panels of random genome-wide SNPs for predicting and estimating Native American ancestry and admixture levels. These AIMs have greater New World vs. Old World specificity than previous AIMs sets. We identify highly-divergent New World SNPs that coincide with high-frequency haplotypes found at similar frequencies in all populations examined, including the HGDP Pima, Maya, Colombian, Karitiana, and Surui American populations. Some of these regions are potential candidates for positive selection. European admixture in the Bolivian sample is approximately 12%, though individual estimates range from 0-48%. We estimate that the admixture occurred ~360-384 years ago. Little evidence of European or African admixture was found in Totonac individuals. Bolivians with pre-Columbian mtDNA and Y-chromosome haplogroups had 5-30% autosomal European ancestry, demonstrating the limitations of Y-chromosome and mtDNA haplogroups and the need for autosomal ancestry informative markers for assessing ancestry in admixed populations.


Assuntos
Indígena Americano ou Nativo do Alasca/genética , Bolívia/etnologia , DNA Mitocondrial , Emigração e Imigração , Genética Populacional , Humanos , México/etnologia , Filogeografia , Polimorfismo de Nucleotídeo Único , Seleção Genética
12.
Am J Phys Anthropol ; 147(1): 35-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22024980

RESUMO

Recent analyses of mitochondrial genomes from Native Americans have brought the overall number of recognized maternal founding lineages from just four to a current count of 15. However, because of their relative low frequency, almost nothing is known for some of these lineages. This leaves a considerable void in understanding the events that led to the colonization of the Americas following the Last Glacial Maximum (LGM). In this study, we identified and completely sequenced 14 mitochondrial DNAs belonging to one extremely rare Native American lineage known as haplogroup C4c. Its age and geographical distribution raise the possibility that C4c marked the Paleo-Indian group(s) that entered North America from Beringia through the ice-free corridor between the Laurentide and Cordilleran ice sheets. The similarities in ages andgeographical distributions for C4c and the previously analyzed X2a lineage provide support to the scenario of a dual origin for Paleo-Indians. Taking into account that C4c is deeply rooted in the Asian portion of the mtDNA phylogeny and is indubitably of Asian origin, the finding that C4c and X2a are characterized by parallel genetic histories definitively dismisses the controversial hypothesis of an Atlantic glacial entry route into North America.


Assuntos
Povo Asiático/genética , DNA Mitocondrial/genética , Emigração e Imigração/história , Haplótipos/genética , Indígenas Norte-Americanos/genética , Canadá , Colômbia , Variação Genética/genética , Genética Populacional , História Antiga , Humanos , Filogenia , Análise de Sequência de DNA , Estados Unidos
13.
Genomics ; 96(4): 199-210, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20643205

RESUMO

High-throughput genotyping data are useful for making inferences about human evolutionary history. However, the populations sampled to date are unevenly distributed, and some areas (e.g., South and Central Asia) have rarely been sampled in large-scale studies. To assess human genetic variation more evenly, we sampled 296 individuals from 13 worldwide populations that are not covered by previous studies. By combining these samples with a data set from our laboratory and the HapMap II samples, we assembled a final dataset of ~250,000 SNPs in 850 individuals from 40 populations. With more uniform sampling, the estimate of global genetic differentiation (F(ST)) substantially decreases from ~16% with the HapMap II samples to ~11%. A panel of copy number variations typed in the same populations shows patterns of diversity similar to the SNP data, with highest diversity in African populations. This unique sample collection also permits new inferences about human evolutionary history. The comparison of haplotype variation among populations supports a single out-of-Africa migration event and suggests that the founding population of Eurasia may have been relatively large but isolated from Africans for a period of time. We also found a substantial affinity between populations from central Asia (Kyrgyzstani and Mongolian Buryat) and America, suggesting a central Asian contribution to New World founder populations.


Assuntos
Variação Genética , Genética Médica/estatística & dados numéricos , Genética Médica/tendências , Genética Populacional/métodos , Variações do Número de Cópias de DNA , Demografia/métodos , Demografia/estatística & dados numéricos , Demografia/tendências , Especiação Genética , Variação Genética/fisiologia , Genética Médica/métodos , Genética Populacional/estatística & dados numéricos , Genética Populacional/tendências , Estudo de Associação Genômica Ampla/métodos , Estudo de Associação Genômica Ampla/estatística & dados numéricos , Estudo de Associação Genômica Ampla/tendências , Genótipo , Geografia , Haplótipos , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único , Estudos de Amostragem
14.
Genes (Basel) ; 12(9)2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34573435

RESUMO

Mexico is a rich source for anthropological and population genetic studies with high diversity in ethnic and linguistic groups. The country witnessed the rise and fall of major civilizations, including the Maya and Aztec, but resulting from European colonization, the population landscape has dramatically changed. Today, the majority of Mexicans do not identify themselves as Indigenous but as admixed, and appear to have very little in common with their pre-Columbian predecessors. However, when the maternally inherited mitochondrial (mt)DNA is investigated in the modern Mexican population, this is not the case. Control region sequences of 2021 samples deriving from all over the country revealed an overwhelming Indigenous American legacy, with almost 90% of mtDNAs belonging to the four major pan-American haplogroups A2, B2, C1, and D1. This finding supports a very low European contribution to the Mexican gene pool by female colonizers and confirms the effectiveness of employing uniparental markers as a tool to reconstruct a country's history. In addition, the distinct frequency and dispersal patterns of Indigenous American and West Eurasian clades highlight the benefit such large and country-wide databases provide for studying the impact of colonialism from a female perspective and population stratification. The importance of geographical database subsets not only for forensic application is clearly demonstrated.


Assuntos
DNA Mitocondrial/genética , Genética Populacional , População Negra/genética , Feminino , Pool Gênico , Haplótipos , Humanos , Masculino , México , Filogeografia , Controle de Qualidade , População Branca/genética , Indígena Americano ou Nativo do Alasca/genética
15.
Front Genet ; 12: 819337, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069708

RESUMO

Mongolia is located in a strategic position at the eastern edge of the Eurasian Steppe. Nomadic populations moved across this wide area for millennia before developing more sedentary communities, extended empires, and complex trading networks, which connected western Eurasia and eastern Asia until the late Medieval period. We provided a fine-grained portrait of the mitochondrial DNA (mtDNA) variation observed in present-day Mongolians and capable of revealing gene flows and other demographic processes that took place in Inner Asia, as well as in western Eurasia. The analyses of a novel dataset (N = 2,420) of mtDNAs highlighted a clear matrilineal differentiation within the country due to a mixture of haplotypes with eastern Asian (EAs) and western Eurasian (WEu) origins, which were differentially lost and preserved. In a wider genetic context, the prevalent EAs contribution, larger in eastern and central Mongolian regions, revealed continuous connections with neighboring Asian populations until recent times, as attested by the geographically restricted haplotype-sharing likely facilitated by the Genghis Khan's so-called Pax Mongolica. The genetic history beyond the WEu haplogroups, notably detectable on both sides of Mongolia, was more difficult to explain. For this reason, we moved to the analysis of entire mitogenomes (N = 147). Although it was not completely possible to identify specific lineages that evolved in situ, two major changes in the effective (female) population size were reconstructed. The more recent one, which began during the late Pleistocene glacial period and became steeper in the early Holocene, was probably the outcome of demographic events connected to western Eurasia. The Neolithic growth could be easily explained by the diffusion of dairy pastoralism, as already proposed, while the late glacial increase indicates, for the first time, a genetic connection with western Eurasian refuges, as supported by the unusual high frequency and internal sub-structure in Mongolia of haplogroup H1, a well-known post-glacial marker in Europe. Bronze Age events, without a significant demographic impact, might explain the age of some mtDNA haplogroups. Finally, a diachronic comparison with available ancient mtDNAs made it possible to link six mitochondrial lineages of present-day Mongolians to the timeframe and geographic path of the Silk Route.

16.
Ann Hum Genet ; 74(2): 184-8, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20201939

RESUMO

Heart failure is a leading cause of death of people in South Asia, and cardiomyopathy is a major cause of heart failure. Myosin binding protein C (MYBPC3) is expressed in the heart muscle, where it regulates the cardiac response to adrenergic stimulation and is important for the structural integrity of the sarcomere. Mutations in the MYBPC3 gene are associated with hypertrophic or dilated cardiomyopathies. A 25-base-pair deletion in intron 32 causes skipping of the downstream exon and is associated with familial cardiomyopathy. To date, this deletion is found primarily in India and South Asia, although it is also found at low frequency in Southeast Asia. In order to better characterise the distribution of this variant, we determined its frequency in 447 individuals from 19 populations, including 10 populations from India and neighbouring populations from Pakistan and Nepal. The deletion frequency is over 8% in some of our Indian samples, and it is not present in any of the populations we sampled outside of India. The differences in the deletion frequencies among populations in India are consistent with patterns of variation previously reported and with patterns we observed among Indian populations based on high-density SNP chip data. Our results indicate that the MYBPC3 deletion is primarily found among Indian populations and that its distribution is consistent with genome-wide patterns of variation in India.


Assuntos
Cardiomiopatias/genética , Proteínas de Transporte/genética , Deleção de Genes , Cardiomiopatias/metabolismo , Humanos , Índia , Nepal , Paquistão
17.
Croat Med J ; 50(3): 239-49, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19480020

RESUMO

AIM: To determine the human Y-chromosome haplogroup backgrounds of intermediate-sized variant alleles displayed by short tandem repeat (STR) loci DYS392, DYS449, and DYS385, and to evaluate the potential of each intermediate variant to elucidate new phylogenetic substructure within the human Y-chromosome haplogroup tree. METHODS: Molecular characterization of lineages was achieved using a combination of Y-chromosome haplogroup defining binary polymorphisms and up to 37 short tandem repeat loci. DNA sequencing and median-joining network analyses were used to evaluate Y-chromosome lineages displaying intermediate variant alleles. RESULTS: We show that DYS392.2 occurs on a single haplogroup background, specifically I1*-M253, and likely represents a new phylogenetic subdivision in this European haplogroup. Intermediate variants DYS449.2 and DYS385.2 both occur on multiple haplogroup backgrounds, and when evaluated within specific haplogroup contexts, delineate new phylogenetic substructure, with DYS449.2 being informative within haplogroup A-P97 and DYS385.2 in haplogroups D-M145, E1b1a-M2, and R1b*-M343. Sequence analysis of variant alleles observed within the various haplogroup backgrounds showed that the nature of the intermediate variant differed, confirming the mutations arose independently. CONCLUSIONS: Y-chromosome short tandem repeat intermediate variant alleles, while relatively rare, typically occur on multiple haplogroup backgrounds. This distribution indicates that such mutations arise at a rate generally intermediate to those of binary markers and STR loci. As a result, intermediate-sized Y-STR variants can reveal phylogenetic substructure within the Y-chromosome phylogeny not currently detected by either binary or Y-STR markers alone, but only when such variants are evaluated within a haplogroup context.


Assuntos
Cromossomos Humanos Y/genética , Repetições de Microssatélites/genética , Filogenia , Haplótipos , Humanos , Análise de Sequência de DNA
18.
Forensic Sci Int Genet ; 42: 1-7, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31195186

RESUMO

Although autosomal DNA testing has been available for a number of years, its use to reconstruct genetic profiles of people that lived centuries in the past is relatively recent and there are no published cases where it was employed to verify a kinship relation, likely to be an alleged paternity, that occurred one and a half century ago. DNA testing has already been employed to study the ancestry and posterity of Joseph Smith Jr., founder of the Latter-day Saint (Mormon) movement. Thanks to information found on the paternally inherited Y chromosome, a number of alleged paternities have been disproved, but obviously this analysis is not effective for alleged daughters. Likewise, his reconstructed mitogenome sequence, reported here for the first time, provides information about his maternal ancestry, but is useless in any paternity questions due to the strict maternal inheritance. Among all the children attributed to Joseph Smith Jr., Josephine Lyon, born in 1844, is perhaps the most frequently mentioned. In the current study, 56 individuals, mostly direct descendants of Joseph Smith Jr. and Josephine Lyon, had their autosomal DNA tested to verify Josephine's biological paternity. Nearly 600,000 autosomal SNPs from each subject were typed and detailed genealogical data were compiled. The absence of shared DNA between Josephine's grandson and Joseph Smith Jr.'s five great-grandchildren together with various amounts of autosomal DNA shared by the same individual with four other relatives of Windsor Lyon is a clear indication that Josephine was not related to the Smith, but to the Lyon's family. These inferences were also verified using kinship analyses and likelihood ratio calculations.


Assuntos
Impressões Digitais de DNA , Paternidade , Linhagem , Polimorfismo de Nucleotídeo Único , Igreja de Jesus Cristo dos Santos dos Últimos Dias/história , DNA Mitocondrial/genética , Triagem e Testes Direto ao Consumidor , Pessoas Famosas , Feminino , Genótipo , História do Século XIX , Humanos , Funções Verossimilhança , Masculino , Casamento , Estados Unidos
19.
Hum Genomics ; 2(4): 212-35, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16460647

RESUMO

The ability to infer personal genetic ancestry is being increasingly utilised in certain medical and forensic situations. Herein, the unsupervised Bayesian clustering algorithms structure, is employed to analyse 377 autosomal short tandem repeats typed on 1,056 individuals from the Centre d'Etude du Polymorphisme Humain Human Diversity Panel. Individuals of known geographical origin were hierarchically classified into a framework of increasingly homogeneous clusters to serve as reference populations into which individuals of unknown ancestry can be assigned. The groupings were characterised by the geographical affinities of cluster members and the accuracy of these procedures was verified using several genetic indices. Fine-scale substructure was detectable beyond the broad population level classifications that previously have been explored in this dataset. Metrics indicated that within certain lines, the strongest structuring signals were detected at the leaves of the hierarchy where lineage-specific groupings were identified. The accuracy of unknown assignment was assessed at each level of the hierarchy using a 'leave one out' strategy in which each individual was stripped of cluster membership and then re-assigned using the supervised Bayesian clustering algorithm implemented in GeneClass2. Although most clusters at all levels of resolution experienced highly accurate assignment, a decline was observed in the finer levels due to the mixed membership characteristics of some individuals. The parameters defined by this study allowed for assignment of unknown individuals to genetically defined clusters with measured likelihood. Shared ancestry data can then be inferred for the unknown individual.


Assuntos
Genética Populacional/métodos , Grupos Populacionais/genética , Algoritmos , Teorema de Bayes , Genética Médica , Geografia , Humanos , Valores de Referência , Sequências Repetitivas de Ácido Nucleico
20.
Croat Med J ; 48(4): 450-9, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17696299

RESUMO

AIM: To determine the human Y-chromosome haplogroup backgrounds of non-consensus DYS458.2 short tandem repeat alleles and evaluate their phylogenetic substructure and frequency in representative samples from the Middle East, Europe, and Pakistan. METHODS: Molecular characterization of lineages was achieved using a combination of Y-chromosome haplogroup defining binary polymorphisms and up to 37 short tandem repeat loci, including DYS388 to construct haplotypes. DNA sequencing of the DYS458 locus and median-joining network analyses were used to evaluate Y-chromosome lineages displaying the DYS458.2 motif. RESULTS: We showed that the DYS458.2 allelic innovation arose independently on at least two distinctive binary haplogroup backgrounds and possibly a third as well. The partial allele length pattern was fixed in all haplogroup J1 chromosomes examined, including its known rare sub-haplogroups. Within the alternative R1b3 associated M405 defined sub-haplogroup, both DYS458.0 and DYS458.2 allele classes occurred. A single chromosome also allocated to the R1b3-M269*(xM405) classification. The physical position of the partial insertion/deletion occurrence within the normal tetramer tract differed distinctly in each haplogroup context. CONCLUSIONS: While unusual DYS458.2 alleles are informative, additional information for other linked polymorphic loci is required when using such non-conforming alleles to infer haplogroup background and common ancestry.


Assuntos
Cromossomos Humanos Y/genética , Frequência do Gene , Haplótipos , Repetições de Microssatélites , Alelos , Europa (Continente) , Genética Populacional , Humanos , Paquistão , Mutação Puntual , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Turquia
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