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1.
Science ; 381(6657): eade4995, 2023 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-37535739

RESUMEN

Few African Americans have been able to trace family lineages back to ancestors who died before the 1870 United States Census, the first in which all Black people were listed by name. We analyzed 27 individuals from Maryland's Catoctin Furnace African American Cemetery (1774-1850), identifying 41,799 genetic relatives among consenting research participants in 23andMe, Inc.'s genetic database. One of the highest concentrations of close relatives is in Maryland, suggesting that descendants of the Catoctin individuals remain in the area. We find that many of the Catoctin individuals derived African ancestry from the Wolof or Kongo groups and European ancestry from Great Britain and Ireland. This study demonstrates the power of joint analysis of historical DNA and large datasets generated through direct-to-consumer ancestry testing.


Asunto(s)
Negro o Afroamericano , Bases de Datos Genéticas , Humanos , Negro o Afroamericano/genética , Irlanda , Maryland , Estados Unidos , Análisis de Secuencia de ADN
2.
Nat Commun ; 12(1): 7283, 2021 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-34907168

RESUMEN

Relatively little is known about Nubia's genetic landscape prior to the influence of the Islamic migrations that began in the late 1st millennium CE. Here, we increase the number of ancient individuals with genome-level data from the Nile Valley from three to 69, reporting data for 66 individuals from two cemeteries at the Christian Period (~650-1000 CE) site of Kulubnarti, where multiple lines of evidence suggest social stratification. The Kulubnarti Nubians had ~43% Nilotic-related ancestry (individual variation between ~36-54%) with the remaining ancestry consistent with being  introduced through Egypt and ultimately deriving from an ancestry pool like that found in the Bronze and Iron Age Levant. The Kulubnarti gene pool - shaped over a millennium - harbors disproportionately female-associated West Eurasian-related ancestry. Genetic similarity among individuals from the two cemeteries supports a hypothesis of social division without genetic distinction. Seven pairs of inter-cemetery relatives suggest fluidity between cemetery groups. Present-day Nubians are not directly descended from the Kulubnarti Nubians, attesting to additional genetic input since the Christian Period.


Asunto(s)
Estatus Social , Egipto , Femenino , Fósiles , Pool de Genes , Flujo Genético , Variación Genética , Genética de Población , Genoma Humano/genética , Historia Antigua , Humanos , Masculino , Caracteres Sexuales , Sudán
4.
Cell ; 181(5): 1131-1145.e21, 2020 05 28.
Artículo en Inglés | MEDLINE | ID: mdl-32386546

RESUMEN

There are many unanswered questions about the population history of the Central and South Central Andes, particularly regarding the impact of large-scale societies, such as the Moche, Wari, Tiwanaku, and Inca. We assembled genome-wide data on 89 individuals dating from ∼9,000-500 years ago (BP), with a particular focus on the period of the rise and fall of state societies. Today's genetic structure began to develop by 5,800 BP, followed by bi-directional gene flow between the North and South Highlands, and between the Highlands and Coast. We detect minimal admixture among neighboring groups between ∼2,000-500 BP, although we do detect cosmopolitanism (people of diverse ancestries living side-by-side) in the heartlands of the Tiwanaku and Inca polities. We also highlight cases of long-range mobility connecting the Andes to Argentina and the Northwest Andes to the Amazon Basin. VIDEO ABSTRACT.


Asunto(s)
Antropología/métodos , ADN Antiguo/análisis , Flujo Génico/genética , América Central , ADN Mitocondrial/genética , Flujo Génico/fisiología , Genética de Población/métodos , Haplotipos , Humanos , Análisis de Secuencia de ADN , América del Sur
6.
Cureus ; 12(1): e6689, 2020 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-32104626

RESUMEN

Tinea versicolor (TV), or pityriasis versicolor, is one of the most commonly occurring superficial mycoses. Typically, this condition is characterized by fine scaly hyper or hypopigmented macules and patches distributed on the trunk and upper extremities. Diagnosis is often based on clinical presentation. A Wood's lamp examination or potassium hydroxide (KOH) preparation test is performed for confirmation. To date, numerous morphologic variants of this condition have been described. Here we present an inverse papular variant that, to our knowledge, has only been previously reported once. This case represents another unique presentation of TV and serves to highlight the clinical variety of this common mycosis.

7.
Nat Ecol Evol ; 4(3): 334-345, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32094539

RESUMEN

Steppe-pastoralist-related ancestry reached Central Europe by at least 2500 BC, whereas Iranian farmer-related ancestry was present in Aegean Europe by at least 1900 BC. However, the spread of these ancestries into the western Mediterranean, where they have contributed to many populations that live today, remains poorly understood. Here, we generated genome-wide ancient-DNA data from the Balearic Islands, Sicily and Sardinia, increasing the number of individuals with reported data from 5 to 66. The oldest individual from the Balearic Islands (~2400 BC) carried ancestry from steppe pastoralists that probably derived from west-to-east migration from Iberia, although two later Balearic individuals had less ancestry from steppe pastoralists. In Sicily, steppe pastoralist ancestry arrived by ~2200 BC, in part from Iberia; Iranian-related ancestry arrived by the mid-second millennium BC, contemporary to its previously documented spread to the Aegean; and there was large-scale population replacement after the Bronze Age. In Sardinia, nearly all ancestry derived from the island's early farmers until the first millennium BC, with the exception of an outlier from the third millennium BC, who had primarily North African ancestry and who-along with an approximately contemporary Iberian-documents widespread Africa-to-Europe gene flow in the Chalcolithic. Major immigration into Sardinia began in the first millennium BC and, at present, no more than 56-62% of Sardinian ancestry is from its first farmers. This value is lower than previous estimates, highlighting that Sardinia, similar to every other region in Europe, has been a stage for major movement and mixtures of people.


Asunto(s)
Agricultura , ADN Antiguo , Estudio de Asociación del Genoma Completo , África , Antropología , Emigración e Inmigración , Europa (Continente) , Humanos , Irán , Islas , Sicilia , España
8.
Science ; 365(6457)2019 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-31488661

RESUMEN

By sequencing 523 ancient humans, we show that the primary source of ancestry in modern South Asians is a prehistoric genetic gradient between people related to early hunter-gatherers of Iran and Southeast Asia. After the Indus Valley Civilization's decline, its people mixed with individuals in the southeast to form one of the two main ancestral populations of South Asia, whose direct descendants live in southern India. Simultaneously, they mixed with descendants of Steppe pastoralists who, starting around 4000 years ago, spread via Central Asia to form the other main ancestral population. The Steppe ancestry in South Asia has the same profile as that in Bronze Age Eastern Europe, tracking a movement of people that affected both regions and that likely spread the distinctive features shared between Indo-Iranian and Balto-Slavic languages.


Asunto(s)
Pueblo Asiatico/genética , Granjas/historia , Migración Humana/historia , Población/genética , Asia Central , Asia Sudoriental , Flujo Génico , Historia Antigua , Humanos , Irán , Análisis de Secuencia de ADN
9.
Cell ; 179(3): 729-735.e10, 2019 10 17.
Artículo en Inglés | MEDLINE | ID: mdl-31495572

RESUMEN

We report an ancient genome from the Indus Valley Civilization (IVC). The individual we sequenced fits as a mixture of people related to ancient Iranians (the largest component) and Southeast Asian hunter-gatherers, a unique profile that matches ancient DNA from 11 genetic outliers from sites in Iran and Turkmenistan in cultural communication with the IVC. These individuals had little if any Steppe pastoralist-derived ancestry, showing that it was not ubiquitous in northwest South Asia during the IVC as it is today. The Iranian-related ancestry in the IVC derives from a lineage leading to early Iranian farmers, herders, and hunter-gatherers before their ancestors separated, contradicting the hypothesis that the shared ancestry between early Iranians and South Asians reflects a large-scale spread of western Iranian farmers east. Instead, sampled ancient genomes from the Iranian plateau and IVC descend from different groups of hunter-gatherers who began farming without being connected by substantial movement of people.


Asunto(s)
ADN Antiguo/química , Genoma Humano , Migración Humana , Linaje , Población/genética , Pueblo Asiatico/genética , Evolución Molecular , Humanos , Irán , Pakistán
10.
Nat Commun ; 10(1): 3670, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31431628

RESUMEN

Situated at over 5,000 meters above sea level in the Himalayan Mountains, Roopkund Lake is home to the scattered skeletal remains of several hundred individuals of unknown origin. We report genome-wide ancient DNA for 38 skeletons from Roopkund Lake, and find that they cluster into three distinct groups. A group of 23 individuals have ancestry that falls within the range of variation of present-day South Asians. A further 14 have ancestry typical of the eastern Mediterranean. We also identify one individual with Southeast Asian-related ancestry. Radiocarbon dating indicates that these remains were not deposited simultaneously. Instead, all of the individuals with South Asian-related ancestry date to ~800 CE (but with evidence of being deposited in more than one event), while all other individuals date to ~1800 CE. These differences are also reflected in stable isotope measurements, which reveal a distinct dietary profile for the two main groups.


Asunto(s)
Restos Mortales/citología , ADN/genética , Fósiles , Grupos Raciales/genética , Dieta , Migración Humana , Humanos , India , Región Mediterránea , Polimorfismo de Nucleótido Simple/genética , Datación Radiométrica
11.
Nat Ecol Evol ; 3(6): 986-987, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31068681

RESUMEN

In the version of this Article originally published, there were errors in the colour ordering of the legend in Fig. 5b, and in the positions of the target and surrogate populations in Fig. 5c. This has now been corrected. The conclusions of the study are in no way affected. The errors have been corrected in the HTML and PDF versions of the article.

12.
Nat Ecol Evol ; 3(5): 765-771, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30988490

RESUMEN

The roles of migration, admixture and acculturation in the European transition to farming have been debated for over 100 years. Genome-wide ancient DNA studies indicate predominantly Aegean ancestry for continental Neolithic farmers, but also variable admixture with local Mesolithic hunter-gatherers. Neolithic cultures first appear in Britain circa 4000 BC, a millennium after they appeared in adjacent areas of continental Europe. The pattern and process of this delayed British Neolithic transition remain unclear. We assembled genome-wide data from 6 Mesolithic and 67 Neolithic individuals found in Britain, dating 8500-2500 BC. Our analyses reveal persistent genetic affinities between Mesolithic British and Western European hunter-gatherers. We find overwhelming support for agriculture being introduced to Britain by incoming continental farmers, with small, geographically structured levels of hunter-gatherer ancestry. Unlike other European Neolithic populations, we detect no resurgence of hunter-gatherer ancestry at any time during the Neolithic in Britain. Genetic affinities with Iberian Neolithic individuals indicate that British Neolithic people were mostly descended from Aegean farmers who followed the Mediterranean route of dispersal. We also infer considerable variation in pigmentation levels in Europe by circa 6000 BC.


Asunto(s)
ADN Antiguo , Genoma , Europa (Continente) , Humanos , Dinámica Poblacional , Reino Unido
13.
Nat Commun ; 10(1): 590, 2019 02 04.
Artículo en Inglés | MEDLINE | ID: mdl-30713341

RESUMEN

Archaeogenetic studies have described the formation of Eurasian 'steppe ancestry' as a mixture of Eastern and Caucasus hunter-gatherers. However, it remains unclear when and where this ancestry arose and whether it was related to a horizon of cultural innovations in the 4th millennium BCE that subsequently facilitated the advance of pastoral societies in Eurasia. Here we generated genome-wide SNP data from 45 prehistoric individuals along a 3000-year temporal transect in the North Caucasus. We observe a genetic separation between the groups of the Caucasus and those of the adjacent steppe. The northern Caucasus groups are genetically similar to contemporaneous populations south of it, suggesting human movement across the mountain range during the Bronze Age. The steppe groups from Yamnaya and subsequent pastoralist cultures show evidence for previously undetected farmer-related ancestry from different contact zones, while Steppe Maykop individuals harbour additional Upper Palaeolithic Siberian and Native American related ancestry.

14.
Cell ; 175(5): 1185-1197.e22, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30415837

RESUMEN

We report genome-wide ancient DNA from 49 individuals forming four parallel time transects in Belize, Brazil, the Central Andes, and the Southern Cone, each dating to at least ∼9,000 years ago. The common ancestral population radiated rapidly from just one of the two early branches that contributed to Native Americans today. We document two previously unappreciated streams of gene flow between North and South America. One affected the Central Andes by ∼4,200 years ago, while the other explains an affinity between the oldest North American genome associated with the Clovis culture and the oldest Central and South Americans from Chile, Brazil, and Belize. However, this was not the primary source for later South Americans, as the other ancient individuals derive from lineages without specific affinity to the Clovis-associated genome, suggesting a population replacement that began at least 9,000 years ago and was followed by substantial population continuity in multiple regions.


Asunto(s)
Genética de Población/historia , Genoma Humano , América Central , ADN Antiguo/análisis , ADN Mitocondrial/genética , Flujo Génico , Historia Antigua , Humanos , Modelos Teóricos , América del Sur
15.
Science ; 361(6397): 92-95, 2018 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-29773666

RESUMEN

Southeast Asia is home to rich human genetic and linguistic diversity, but the details of past population movements in the region are not well known. Here, we report genome-wide ancient DNA data from 18 Southeast Asian individuals spanning from the Neolithic period through the Iron Age (4100 to 1700 years ago). Early farmers from Man Bac in Vietnam exhibit a mixture of East Asian (southern Chinese agriculturalist) and deeply diverged eastern Eurasian (hunter-gatherer) ancestry characteristic of Austroasiatic speakers, with similar ancestry as far south as Indonesia providing evidence for an expansive initial spread of Austroasiatic languages. By the Bronze Age, in a parallel pattern to Europe, sites in Vietnam and Myanmar show close connections to present-day majority groups, reflecting substantial additional influxes of migrants.


Asunto(s)
Genoma Humano , Migración Humana/historia , Lenguaje/historia , Agricultura/historia , Asia Sudoriental , Pueblo Asiatico/genética , ADN Antiguo , Variación Genética , Historia Antigua , Humanos , Datación Radiométrica
16.
Curr Biol ; 28(7): 1157-1165.e7, 2018 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-29501328

RESUMEN

Ancient DNA from Vanuatu and Tonga dating to about 2,900-2,600 years ago (before present, BP) has revealed that the "First Remote Oceanians" associated with the Lapita archaeological culture were directly descended from the population that, beginning around 5000 BP, spread Austronesian languages from Taiwan to the Philippines, western Melanesia, and eventually Remote Oceania. Thus, ancestors of the First Remote Oceanians must have passed by the Papuan-ancestry populations they encountered in New Guinea, the Bismarck Archipelago, and the Solomon Islands with minimal admixture [1]. However, all present-day populations in Near and Remote Oceania harbor >25% Papuan ancestry, implying that additional eastward migration must have occurred. We generated genome-wide data for 14 ancient individuals from Efate and Epi Islands in Vanuatu from 2900-150 BP, as well as 185 present-day individuals from 18 islands. We find that people of almost entirely Papuan ancestry arrived in Vanuatu by around 2300 BP, most likely reflecting migrations a few hundred years earlier at the end of the Lapita period, when there is also evidence of changes in skeletal morphology and cessation of long-distance trade between Near and Remote Oceania [2, 3]. Papuan ancestry was subsequently diluted through admixture but remains at least 80%-90% in most islands. Through a fine-grained analysis of ancestry profiles, we show that the Papuan ancestry in Vanuatu derives from the Bismarck Archipelago rather than the geographically closer Solomon Islands. However, the Papuan ancestry in Polynesia-the most remote Pacific islands-derives from different sources, documenting a third stream of migration from Near to Remote Oceania.


Asunto(s)
ADN Antiguo/análisis , Genética de Población , Genoma Humano , Migración Humana/estadística & datos numéricos , Nativos de Hawái y Otras Islas del Pacífico/genética , Dinámica Poblacional , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Oceanía , Filogenia
18.
Nature ; 555(7695): 197-203, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29466330

RESUMEN

Farming was first introduced to Europe in the mid-seventh millennium bc, and was associated with migrants from Anatolia who settled in the southeast before spreading throughout Europe. Here, to understand the dynamics of this process, we analysed genome-wide ancient DNA data from 225 individuals who lived in southeastern Europe and surrounding regions between 12000 and 500 bc. We document a west-east cline of ancestry in indigenous hunter-gatherers and, in eastern Europe, the early stages in the formation of Bronze Age steppe ancestry. We show that the first farmers of northern and western Europe dispersed through southeastern Europe with limited hunter-gatherer admixture, but that some early groups in the southeast mixed extensively with hunter-gatherers without the sex-biased admixture that prevailed later in the north and west. We also show that southeastern Europe continued to be a nexus between east and west after the arrival of farmers, with intermittent genetic contact with steppe populations occurring up to 2,000 years earlier than the migrations from the steppe that ultimately replaced much of the population of northern Europe.


Asunto(s)
Agricultores/historia , Genoma Humano/genética , Genómica , Migración Humana/historia , Agricultura/historia , Asia/etnología , ADN Antiguo , Europa (Continente) , Femenino , Genética de Población , Pradera , Historia Antigua , Humanos , Masculino , Distribución por Sexo
19.
Nature ; 555(7695): 190-196, 2018 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-29466337

RESUMEN

From around 2750 to 2500 bc, Bell Beaker pottery became widespread across western and central Europe, before it disappeared between 2200 and 1800 bc. The forces that propelled its expansion are a matter of long-standing debate, and there is support for both cultural diffusion and migration having a role in this process. Here we present genome-wide data from 400 Neolithic, Copper Age and Bronze Age Europeans, including 226 individuals associated with Beaker-complex artefacts. We detected limited genetic affinity between Beaker-complex-associated individuals from Iberia and central Europe, and thus exclude migration as an important mechanism of spread between these two regions. However, migration had a key role in the further dissemination of the Beaker complex. We document this phenomenon most clearly in Britain, where the spread of the Beaker complex introduced high levels of steppe-related ancestry and was associated with the replacement of approximately 90% of Britain's gene pool within a few hundred years, continuing the east-to-west expansion that had brought steppe-related ancestry into central and northern Europe over the previous centuries.


Asunto(s)
Evolución Cultural/historia , Genoma Humano/genética , Genómica , Migración Humana/historia , Cromosomas Humanos Y/genética , ADN Antiguo , Europa (Continente) , Pool de Genes , Genética de Población , Haplotipos , Historia Antigua , Humanos , Masculino , Análisis Espacio-Temporal
20.
Nature ; 551(7680): 368-372, 2017 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-29144465

RESUMEN

Ancient DNA studies have established that Neolithic European populations were descended from Anatolian migrants who received a limited amount of admixture from resident hunter-gatherers. Many open questions remain, however, about the spatial and temporal dynamics of population interactions and admixture during the Neolithic period. Here we investigate the population dynamics of Neolithization across Europe using a high-resolution genome-wide ancient DNA dataset with a total of 180 samples, of which 130 are newly reported here, from the Neolithic and Chalcolithic periods of Hungary (6000-2900 bc, n = 100), Germany (5500-3000 bc, n = 42) and Spain (5500-2200 bc, n = 38). We find that genetic diversity was shaped predominantly by local processes, with varied sources and proportions of hunter-gatherer ancestry among the three regions and through time. Admixture between groups with different ancestry profiles was pervasive and resulted in observable population transformation across almost all cultural transitions. Our results shed new light on the ways in which gene flow reshaped European populations throughout the Neolithic period and demonstrate the potential of time-series-based sampling and modelling approaches to elucidate multiple dimensions of historical population interactions.


Asunto(s)
Agricultores/historia , Flujo Génico/genética , Variación Genética , Migración Humana/historia , ADN Antiguo/análisis , Conjuntos de Datos como Asunto , Femenino , Alemania , Historia Antigua , Humanos , Hungría , Masculino , Dinámica Poblacional , España , Análisis Espacio-Temporal
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