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1.
Cell ; 186(14): 2977-2994.e23, 2023 07 06.
Artículo en Inglés | MEDLINE | ID: mdl-37343560

RESUMEN

Comparative studies of great apes provide a window into our evolutionary past, but the extent and identity of cellular differences that emerged during hominin evolution remain largely unexplored. We established a comparative loss-of-function approach to evaluate whether human cells exhibit distinct genetic dependencies. By performing genome-wide CRISPR interference screens in human and chimpanzee pluripotent stem cells, we identified 75 genes with species-specific effects on cellular proliferation. These genes comprised coherent processes, including cell-cycle progression and lysosomal signaling, which we determined to be human-derived by comparison with orangutan cells. Human-specific robustness to CDK2 and CCNE1 depletion persisted in neural progenitor cells and cerebral organoids, supporting the G1-phase length hypothesis as a potential evolutionary mechanism in human brain expansion. Our findings demonstrate that evolutionary changes in human cells reshaped the landscape of essential genes and establish a platform for systematically uncovering latent cellular and molecular differences between species.


Asunto(s)
Hominidae , Células-Madre Neurales , Células Madre Pluripotentes , Células Madre , Animales , Humanos , Pan troglodytes/genética
2.
Cell ; 184(7): 1706-1723.e24, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33761327

RESUMEN

The recently enriched genomic history of Indigenous groups in the Americas is still meager concerning continental Central America. Here, we report ten pre-Hispanic (plus two early colonial) genomes and 84 genome-wide profiles from seven groups presently living in Panama. Our analyses reveal that pre-Hispanic demographic events contributed to the extensive genetic structure currently seen in the area, which is also characterized by a distinctive Isthmo-Colombian Indigenous component. This component drives these populations on a specific variability axis and derives from the local admixture of different ancestries of northern North American origin(s). Two of these ancestries were differentially associated to Pleistocene Indigenous groups that also moved into South America, leaving heterogenous genetic footprints. An additional Pleistocene ancestry was brought by a still unsampled population of the Isthmus (UPopI) that remained restricted to the Isthmian area, expanded locally during the early Holocene, and left genomic traces up to the present day.


Asunto(s)
Indio Americano o Nativo de Alaska/genética , Arqueología , Genómica/métodos , Indio Americano o Nativo de Alaska/clasificación , ADN Mitocondrial/genética , Variación Genética , Genoma Humano , Haplotipos , Humanos , Filogenia
3.
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
4.
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
5.
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
6.
Proc Natl Acad Sci U S A ; 121(22): e2402159121, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38739836

RESUMEN

The aryl hydrocarbon receptor (AHR) is a transcription factor that has many functions in mammals. Its best known function is that it binds aromatic hydrocarbons and induces the expression of cytochrome P450 genes, which encode enzymes that metabolize aromatic hydrocarbons and other substrates. All present-day humans carry an amino acid substitution at position 381 in the AHR that occurred after the divergence of modern humans from Neandertals and Denisovans. Previous studies that have expressed the ancestral and modern versions of AHR from expression vectors have yielded conflicting results with regard to their activities. Here, we use genome editing to modify the endogenous AHR gene so that it encodes to the ancestral, Neandertal-like AHR protein in human cells. In the absence of exogenous ligands, the expression of AHR target genes is higher in cells expressing the ancestral AHR than in cells expressing the modern AHR, and similar to the expression in chimpanzee cells. Furthermore, the modern human AHR needs higher doses of three ligands than the ancestral AHR to induce the expression of target genes. Thus, the ability of AHR to induce the expression of many of its target genes is reduced in modern humans.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Edición Génica , Receptores de Hidrocarburo de Aril , Receptores de Hidrocarburo de Aril/genética , Receptores de Hidrocarburo de Aril/metabolismo , Humanos , Edición Génica/métodos , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Evolución Molecular , Pan troglodytes/genética , Hombre de Neandertal/genética , Ligandos
7.
Proc Natl Acad Sci U S A ; 121(33): e2405653121, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39110728

RESUMEN

How does social complexity depend on population size and cultural transmission? Kinship structures in traditional societies provide a fundamental illustration, where cultural rules between clans determine people's marriage possibilities. Here, we propose a simple model of kinship interactions that considers kin and in-law cooperation and sexual rivalry. In this model, multiple societies compete. Societies consist of multiple families with different cultural traits and mating preferences. These values determine interactions and hence the growth rate of families and are transmitted to offspring with mutations. Through a multilevel evolutionary simulation, family traits and preferences are grouped into multiple clans with interclan mating preferences. It illustrates the emergence of kinship structures as the spontaneous formation of interdependent cultural associations. Emergent kinship structures are characterized by the cycle length of marriage exchange and the number of cycles in society. We numerically and analytically clarify their parameter dependence. The relative importance of cooperation versus rivalry determines whether attraction or repulsion exists between families. Different structures evolve as locally stable attractors. The probabilities of formation and collapse of complex structures depend on the number of families and the mutation rate, showing characteristic scaling relationships. It is now possible to explore macroscopic kinship structures based on microscopic interactions, together with their environmental dependence and the historical causality of their evolution. We propose the basic causal mechanism of the formation of typical human social structures by referring to ethnographic observations and concepts from statistical physics and multilevel evolution. Such interdisciplinary collaboration will unveil universal features in human societies.


Asunto(s)
Matrimonio , Densidad de Población , Humanos , Tasa de Mutación , Familia , Evolución Cultural , Masculino , Mutación , Femenino , Modelos Teóricos , Cultura
8.
Nature ; 633(8028): 19-20, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39179781
9.
Nature ; 2024 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-39443760
10.
Nature ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232222
11.
Nature ; 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143276
12.
Nature ; 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39384922
13.
Nature ; 626(8001): 955-956, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38383642
15.
Nature ; 2024 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-38448532
17.
Nature ; 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467819
19.
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