title: Microcephalin, a gene regulating brain size, continues to evolve adaptively in humans.
abstract: The gene Microcephalin (MCPH1) regulates brain size and has evolved under strong positive selection in the human evolutionary lineage. We show that one genetic variant of Microcephalin in modern humans, which arose approximately 37,000 years ago, increased in frequency too rapidly to be compatible with neutral drift. This indicates that it has spread under strong positive selection, although the exact nature of the selection is unknown. The finding that an important brain gene has continued to evolve adaptively in anatomically modern humans suggests the ongoing evolutionary plasticity of the human brain. It also makes Microcephalin an attractive candidate locus for studying the genetics of human variation in brain-related phenotypes.
authors.affiliation: Howard Hughes Medical Institute, Department of Human Genetics, University of Chicago, Chicago, IL 60637, USA.
authors.forename: Patrick D
authors.initials: PD
authors.lastname: Evans
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Gilbert
authors.forename: Nitzan
authors.initials: N
authors.lastname: Mekel-Bobrov
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Vallender
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Anderson
authors.forename: Leila M
authors.initials: LM
authors.lastname: Vaez-Azizi
authors.forename: Sarah A
authors.initials: SA
authors.lastname: Tishkoff
authors.forename: Richard R
authors.initials: RR
authors.lastname: Hudson
authors.forename: Bruce T
authors.initials: BT
authors.lastname: Lahn
mesh_terms: D000220:Adaptation, Biological; D000483:Alleles; D019943:Amino Acid Substitution; D044466:Asian People / Q000235:genetics; D005075:Biological Evolution; D044383:Black People / Q000235:genetics; D001921:Brain / Q000033:anatomy & histology* / Q000502:physiology; D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; D005091:Exons; D005785:Gene Conversion; D005787:Gene Frequency; D014644:Genetic Variation; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D015810:Linkage Disequilibrium; D008831:Microcephaly / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics*; D009929:Organ Size; D011110:Polymorphism, Genetic; D011995:Recombination, Genetic; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA; D013995:Time; D044465:White People / Q000235:genetics
chemical_list: D018797:Cell Cycle Proteins; D003598:Cytoskeletal Proteins; C460645:MCPH1 protein, human; D009419:Nerve Tissue Proteins