Meeting Abstract

P1.79  Monday, Jan. 4  Genomic Architecture of Adaptive Radiation: the Role for Gene Duplication in African Cichlid Fishes MACHADO, Heather*; JOYCE, Domino; LUNT, David; RENN, Suzy; Reed College, Portland OR; University of Hull, UK; University of Hull, UK; Reed College, Portland OR renns@reed.edu

The adaptive radiations of African cichlid fishes offer an elegant system with which to study the processes that influence the ever-changing diversity of life. Specifically, these fish provide several independent, recent and rapid diversifications accompanied by some lineages that have existed in relative stasis. Through comparison of radiated and non-radiated lineages we look at how one specific process, gene duplication, may contribute to these phenomenal radiations and to the evolution of adaptive phenotypes in general. Using array based comparative genomic hybridizations (CGH) we compare the prevalence of gene duplication in three Lake Malawi species (Metriaclima estherae, Protomelas similis, Rhamphochromis chilingali) resulting from three different recent cichlid radiations and one species from a lineage that has not undergone recent radiation (Astatotilapia tweddlei). We found an increased number of duplicated genes in the radiated lineages compared to the non-radiated lineage. Genes found duplicated include major histocompatibility (MHC) genes and pituitary adenylate cyclase activating polypeptide receptor (PAC1), which have previously undergone duplication and may be more prone to duplication, and several others of various function, including cytochrome P450 aromatase (cyp19), nuclear receptor DAX1, and fish virus induced tripartite motif gene (finTRIM gene). The preponderance of gene duplications in the radiated lineages supports the hypothesized role for gene duplication in the adaptive radiation of African cichlids and suggests that gene duplication may be an important process in diversification and speciation in general.