@article {309924, title = {Evolution of human-specific neural SRGAP2 genes by incomplete segmental duplication.}, journal = {Cell}, volume = {149}, year = {2012}, month = {2012 May 11}, pages = {912-22}, abstract = {

Gene duplication is an important source of phenotypic change and adaptive evolution. We leverage a haploid hydatidiform mole to identify highly identical sequences missing from the reference genome, confirming that the cortical development gene Slit-Robo Rho GTPase-activating protein 2 (SRGAP2) duplicated three times exclusively in humans. We show that the promoter and first nine exons of SRGAP2 duplicated from 1q32.1 (SRGAP2A) to 1q21.1 (SRGAP2B) \~{}3.4 million years ago (mya). Two larger duplications later copied SRGAP2B to chromosome 1p12 (SRGAP2C) and to proximal 1q21.1 (SRGAP2D) \~{}2.4 and \~{}1 mya, respectively. Sequence and expression analyses show that SRGAP2C is the most likely duplicate to encode a functional protein and is among the most fixed human-specific duplicate genes. Our data suggest a mechanism where incomplete duplication created a novel gene function-antagonizing parental SRGAP2 function-immediately "at birth" 2-3 mya, which is a time corresponding to the transition from Australopithecus to Homo and the beginning of neocortex expansion.

}, keywords = {Animals, DNA Copy Number Variations, Evolution, Molecular, Female, Genetics, Medical, GTPase-Activating Proteins, Humans, Hydatidiform Mole, In Situ Hybridization, Fluorescence, Mammals, Molecular Sequence Data, Pregnancy, Primates, Segmental Duplications, Genomic}, issn = {1097-4172}, doi = {10.1016/j.cell.2012.03.033}, author = {Dennis, Megan Y and Nuttle, Xander and Sudmant, Peter H and Antonacci, Francesca and Graves, Tina A and Nefedov, Mikhail and Rosenfeld, Jill A and Sajjadian, Saba and Malig, Maika and Kotkiewicz, Holland and Curry, Cynthia J and Shafer, Susan and Shaffer, Lisa G and de Jong, Pieter J and Wilson, Richard K and Eichler, Evan E} }