Genetic variability and population structure of the Japanese sea cucumber, Apostichopus japonicus Selenka, 1867 revealed by microsatellites in Peter the Great Gulf, Sea of Japan

Genetic diversity and population structure of the sea cucumber Apostichopus japonicus from four sampling locations in Peter the Great Gulf, Sea of Japan, were studied using 10 microsatellite loci. In total, 108 alleles were detected among the 159 individuals of sea cucumber. The average Ho and He for all populations per all loci was 0.525 and 0.699, respectively (accounting for null alleles). Departure from the Hardy-Weinberg equilibrium was observed at each locus. On average, values of the inbreeding coefficients were above zero, which is connected with heterozygote deficiency. Samples were separated into two groups during cluster analysis. The study of genetic differentiation between samples revealed a high level of heterogeneity that can be explained by several factors: stochastic processes during larval settlement in a certain location, and differences in selection pressures on quantitative trait loci and the linked microsatellite loci. To further understand the mechanisms contributing to this heterogeneity and population structure, cause and effect relationships between genetic variability and environmental conditions need to be studied.

Automated summary

The genetic diversity and population structure of the sea cucumber Apostichopus japonicus in Peter the Great Gulf, Sea of Japan, were studied. It was found that the population showed high heterogeneity and heterozygote deficiency.