Trio sequencing data provides first direct estimates of heritable mutation load in the commercially important species the Pacific oyster (Crassostrea gigas)

Terrestrial selective breeding programs for food crops serve as a template for ocean-based crops, and are comparatively significantly more advanced in most cases. One consideration for marine organisms and their susceptibility to artificial selection is their mutation rate, which is thought to be among the highest observed for one of aquaculture's most heavily produced crop: bivalves. However, many of the best estimates of heritable mutation load have been indirectly estimated through allozyme or microsatellite inference in the Pacific oyster (Crassostrea gigas). While these studies do have solid theoretical framework to back up their estimates, and observed larval survival associated with so-called 'viability loci' support a high genetic load hypothesis, to date, no trios (two parents and their offspring) have been developed and sequenced for the purposes of gaining a direct estimates of heritable mutation rate. Using Pacific oysters, this study utilized three single parent pairings and randomly selected juvenile individuals from each corresponding family to isolate and sequence individuals in order to empirically estimate heritable mutation rate. The findings herein will inform best breeding practices, and provide the first such study in an aquaculture species with vast commercial importance.