Meeting Abstract

12.5  Saturday, Jan. 4 11:15  A genetic linkage map of the coral Orbicella faveolata produced by 2bRAD genotyping of single larvae SNELLING, J; MEYER, E*; Oregon State University; Oregon State University eli.meyer@science.oregonstate.edu

Scleractinian corals are acutely sensitive to elevated temperatures, prompting widespread concern over their fate during global climate change. Genetic variation in corals’ responses to temperature may in principle support an adaptive response to warming temperatures, but the lack of a complete genome assembly has hampered efforts to identify genomic regions underlying such variation in corals. To help develop resources for genomic analysis of thermal tolerance in corals, we focused on Orbicella (Montastraea) faveolata, a dominant and widely studied component of Caribbean reefs. To evaluate the suitability of 2bRAD for genome-wide genotyping in corals, we first characterized genetic diversity among parental colonies. This analysis genotyped 1.4 Mb per sample, revealing 1 SNP every 228 bp on average, many of which (42%) were suitable for linkage analysis. To demonstrate the reproducibility of 2bRAD genotyping in the small amounts of DNA obtained from individual larvae, we compared genotypes determined from replicate preparations of the same DNA, revealing acceptably low error rates (1 disagreement per 10,727 bp). A population of 100 full-sibling larvae obtained by crossing the most diverse pair of parents was then genotyped using 2bRAD, and linkage groups inferred using JoinMap software. We present the consensus linkage map, along with a bulk-segregant analysis of mortality during development to demonstrate the utility of this map for genomic analysis. We also discuss the potential for linkage analysis to organize scaffolds from shotgun genome assemblies, highlighting an efficient route to chromosome-scale genome assemblies that we expect to be widely applicable in many non-model species.