title: Phylogenetic Analysis Supports a Link between DUF1220 Domain Number and Primate Brain Expansion.
abstract: The expansion of DUF1220 domain copy number during human evolution is a dramatic example of rapid and repeated domain duplication. Although patterns of expression, homology, and disease associations suggest a role in cortical development, this hypothesis has not been robustly tested using phylogenetic methods. Here, we estimate DUF1220 domain counts across 12 primate genomes using a nucleotide Hidden Markov Model. We then test a series of hypotheses designed to examine the potential evolutionary significance of DUF1220 copy number expansion. Our results suggest a robust association with brain size, and more specifically neocortex volume. In contradiction to previous hypotheses, we find a strong association with postnatal brain development but not with prenatal brain development. Our results provide further evidence of a conserved association between specific loci and brain size across primates, suggesting that human brain evolution may have occurred through a continuation of existing processes.
authors.affiliation: Department of Genetics, Evolution & Environment, University College London, United Kingdom.
authors.forename: Fabian
authors.initials: F
authors.lastname: Zimmer
authors.affiliation: Department of Genetics, Evolution & Environment, University College London, United Kingdom stephen.montgomery@cantab.net.
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Montgomery
mesh_terms: D000818:Animals; D001921:Brain / Q000033:anatomy & histology* / Q000254:growth & development; D019143:Evolution, Molecular; D023281:Genomics; D006801:Humans; D008390:Markov Chains; D010802:Phylogeny; D011323:Primates / Q000235:genetics; D017434:Protein Structure, Tertiary / Q000235:genetics*
keywords: DUF1220 domains; NBPF; autistic spectrum disorder; brain evolution; primates