Genetic diversity of the sulfotransferase-like gene and one nonsynonymous SNP associated with growth traits of clam, Meretrix meretrix

The sulfotransferase (SULT) is an important factor in phase II metabolism. Three single nucleotide polymorphisms (SNPs; MmeSUl-696, MmeSUl-714 and MmeSUl-806) were discovered in a SULT-like gene of Meretrix meretrix. A modified allele-specific PCR detection assay was developed to perform polymorphism analysis of the three SNPs in two families and two populations of M. meretrix. Results showed that the genotype of the three SNPs is accordance to the expected Mendelian segregation ratios and conforms to Hardy–Weinberg Equilibrium (HWE) in families and populations, respectively. Moreover, sampled clams (n = 151) from the two populations were tested for the associations between SNPs and growth traits. The single SNP association analysis indicated MmeSUl-806 significantly (P < 0.05) correlated with growth traits of M. meretrix. A further haplotype-trait association analysis confirmed that the three SNPs were in linkage disequilibrium and showed that the haplotype TTG and TCG associated with low growth in the two populations, respectively, which supported that MmeSUl-806 was a growth related marker. This study suggested SULT gene might be a candidate gene related to growth in bivalves and MmeSUl-806 could be a gene marker in linkage map construction and breeding programs of M. meretrix.