Molecular genetics of speciation and human origins

Francisco J. Ayala, Ananías Escalante, Colm O'Hugin, Jan Klein

Research output: Contribution to journalArticle

59 Citations (Scopus)

Abstract

The major histocompatibility complex (MHC) plays a cardinal role in the defense of vertebrates against parasites and other pathogens. In some genes there are extensive and ancient polymorphisms that have passed from ancestral to descendant species and are shared among contemporary species. The polymorphism at the DRB1 locus, represented by 58 known alleles in humans, has existed for at least 30 million years and is shared by humans, apes, and other primates. The coalescence theory of population genetics leads to the conclusion that the DRB1 polymorphism requires that the population ancestral to modern humans has maintained a mean effective size of 100,000 individuals over the 30-million-year persistence of this polymorphism. We explore the possibility of occasional population bottlenecks and conclude that the ancestral population could not have at any time consisted of fewer than several thousand individuals. The MHC polymorphisms exclude the theory claiming, on the basis of mitochondrial DNA polymorphisms, that a constriction down to one or few women occurred in Africa, at the transition from archaic to anatomically modern humans, some 200,000 years ago. The data are consistent with, but do not provide specific support for, the claim that human populations throughout the World were at that time replaced by populations migrating from Africa. The MHC and other molecular polymorphisms are consistent with a 'multiregional' theory of Pleistocene human evolution that proposes regional continuity of human populations since the time of migrations of Homo erectus to the present, with distinctive regional selective pressures and occasional migrations between populations.

Original languageEnglish (US)
Pages (from-to)6787-6794
Number of pages8
JournalProceedings of the National Academy of Sciences of the United States of America
Volume91
Issue number15
DOIs
StatePublished - Jul 19 1994

Fingerprint

Genetic Speciation
Molecular Biology
Population
Major Histocompatibility Complex
Hominidae
Population Genetics
Mitochondrial DNA
Constriction
Primates
Vertebrates
Parasites
Alleles

All Science Journal Classification (ASJC) codes

  • General

Cite this

Ayala, Francisco J. ; Escalante, Ananías ; O'Hugin, Colm ; Klein, Jan. / Molecular genetics of speciation and human origins. In: Proceedings of the National Academy of Sciences of the United States of America. 1994 ; Vol. 91, No. 15. pp. 6787-6794.
@article{3319cf6063ed469e9a68970c1b9f4080,
title = "Molecular genetics of speciation and human origins",
abstract = "The major histocompatibility complex (MHC) plays a cardinal role in the defense of vertebrates against parasites and other pathogens. In some genes there are extensive and ancient polymorphisms that have passed from ancestral to descendant species and are shared among contemporary species. The polymorphism at the DRB1 locus, represented by 58 known alleles in humans, has existed for at least 30 million years and is shared by humans, apes, and other primates. The coalescence theory of population genetics leads to the conclusion that the DRB1 polymorphism requires that the population ancestral to modern humans has maintained a mean effective size of 100,000 individuals over the 30-million-year persistence of this polymorphism. We explore the possibility of occasional population bottlenecks and conclude that the ancestral population could not have at any time consisted of fewer than several thousand individuals. The MHC polymorphisms exclude the theory claiming, on the basis of mitochondrial DNA polymorphisms, that a constriction down to one or few women occurred in Africa, at the transition from archaic to anatomically modern humans, some 200,000 years ago. The data are consistent with, but do not provide specific support for, the claim that human populations throughout the World were at that time replaced by populations migrating from Africa. The MHC and other molecular polymorphisms are consistent with a 'multiregional' theory of Pleistocene human evolution that proposes regional continuity of human populations since the time of migrations of Homo erectus to the present, with distinctive regional selective pressures and occasional migrations between populations.",
author = "Ayala, {Francisco J.} and Anan{\'i}as Escalante and Colm O'Hugin and Jan Klein",
year = "1994",
month = "7",
day = "19",
doi = "10.1073/pnas.91.15.6787",
language = "English (US)",
volume = "91",
pages = "6787--6794",
journal = "Proceedings of the National Academy of Sciences of the United States of America",
issn = "0027-8424",
number = "15",

}

Molecular genetics of speciation and human origins. / Ayala, Francisco J.; Escalante, Ananías; O'Hugin, Colm; Klein, Jan.

In: Proceedings of the National Academy of Sciences of the United States of America, Vol. 91, No. 15, 19.07.1994, p. 6787-6794.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Molecular genetics of speciation and human origins

AU - Ayala, Francisco J.

AU - Escalante, Ananías

AU - O'Hugin, Colm

AU - Klein, Jan

PY - 1994/7/19

Y1 - 1994/7/19

N2 - The major histocompatibility complex (MHC) plays a cardinal role in the defense of vertebrates against parasites and other pathogens. In some genes there are extensive and ancient polymorphisms that have passed from ancestral to descendant species and are shared among contemporary species. The polymorphism at the DRB1 locus, represented by 58 known alleles in humans, has existed for at least 30 million years and is shared by humans, apes, and other primates. The coalescence theory of population genetics leads to the conclusion that the DRB1 polymorphism requires that the population ancestral to modern humans has maintained a mean effective size of 100,000 individuals over the 30-million-year persistence of this polymorphism. We explore the possibility of occasional population bottlenecks and conclude that the ancestral population could not have at any time consisted of fewer than several thousand individuals. The MHC polymorphisms exclude the theory claiming, on the basis of mitochondrial DNA polymorphisms, that a constriction down to one or few women occurred in Africa, at the transition from archaic to anatomically modern humans, some 200,000 years ago. The data are consistent with, but do not provide specific support for, the claim that human populations throughout the World were at that time replaced by populations migrating from Africa. The MHC and other molecular polymorphisms are consistent with a 'multiregional' theory of Pleistocene human evolution that proposes regional continuity of human populations since the time of migrations of Homo erectus to the present, with distinctive regional selective pressures and occasional migrations between populations.

AB - The major histocompatibility complex (MHC) plays a cardinal role in the defense of vertebrates against parasites and other pathogens. In some genes there are extensive and ancient polymorphisms that have passed from ancestral to descendant species and are shared among contemporary species. The polymorphism at the DRB1 locus, represented by 58 known alleles in humans, has existed for at least 30 million years and is shared by humans, apes, and other primates. The coalescence theory of population genetics leads to the conclusion that the DRB1 polymorphism requires that the population ancestral to modern humans has maintained a mean effective size of 100,000 individuals over the 30-million-year persistence of this polymorphism. We explore the possibility of occasional population bottlenecks and conclude that the ancestral population could not have at any time consisted of fewer than several thousand individuals. The MHC polymorphisms exclude the theory claiming, on the basis of mitochondrial DNA polymorphisms, that a constriction down to one or few women occurred in Africa, at the transition from archaic to anatomically modern humans, some 200,000 years ago. The data are consistent with, but do not provide specific support for, the claim that human populations throughout the World were at that time replaced by populations migrating from Africa. The MHC and other molecular polymorphisms are consistent with a 'multiregional' theory of Pleistocene human evolution that proposes regional continuity of human populations since the time of migrations of Homo erectus to the present, with distinctive regional selective pressures and occasional migrations between populations.

UR - http://www.scopus.com/inward/record.url?scp=0028283124&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028283124&partnerID=8YFLogxK

U2 - 10.1073/pnas.91.15.6787

DO - 10.1073/pnas.91.15.6787

M3 - Article

C2 - 8041698

AN - SCOPUS:0028283124

VL - 91

SP - 6787

EP - 6794

JO - Proceedings of the National Academy of Sciences of the United States of America

JF - Proceedings of the National Academy of Sciences of the United States of America

SN - 0027-8424

IS - 15

ER -