Meeting Abstract
P3.190 Tuesday, Jan. 6 Deep segregation of single nucleotide polymorphisms (SNPs) in East African cichlids SWOFFORD, Ross W.*; LOH, Y.H. Eddie; STREELMAN, J. Todd; DI PALMA, Federica; LINDBLAD-TOH, Kerstin; TILAPIA SEQUENCING CONSORTIUM, ; Broad Institute of MIT and Harvard; Georgia Institute of Technology; Georgia Institute of Technology; Broad Institute of MIT and Harvard; Broad Institute of MIT and Harvard; Tilapia Sequencing Consortium swofford@broad.mit.edu
The Broad Institute will sequence the complete genome of the Nile Tilapia and the genomes of two additional cichlids from East Africa. The African cichlids represent classic examples of adaptive radiations, and evolutionary divergence due to natural and sexual selection. Remarkably, the cichlids of Lake Tanganyika have diverged into ~250 species in the past 6-8 million years, and the ~500 Lake Victoria species and the ~700 Lake Malawi species diverged in only the past 1 million years. The cichlids are especially diverse in tissues and systems related to the neural crest (jaws,teeth, pigment), and are valuable model organisms for the study of sex determination, behavior, and speciation. The combination of a sequenced cichlid genome and the wide variety of recently evolved cichlid behaviors and morphological traits will provide a unique opportunity for the study of evolution and the genetic basis of a variety of developmental and ecological traits. The Broad Institute, in collaboration with the research community, carried out a preliminary study to further understand genetic diversity within and among the East African cichlid species flocks. DNA samples from 192 cichlid individuals representing populations from Malawi, Tanganyika, Victoria and associated drainages were genotyped at 132 SNP loci, previously identified from comparison of 5 Malawi individuals. Notably, we observe that a large fraction of SNPs segregate beyond Malawi taxa, deep into the lineages of Lakes Tanganyika and the East African haplochromines. We present proof of concept that these markers are ideal for comparative genomics and the study of cichlid population genetic structure.
