Association analysis of SNPs and diplotype of HSC70-1 gene with growth traits in largemouth bass (Micropterus salmoides)

In order to explore the effects of HSC70-1 gene on growth traits of largemouth bass (Micropterus salmoides) and develop growth-related SNPs, we obtained the cDNA of coding region and the complete sequence of HSC70-1 gene by PCR amplification. The encoding region cDNA sequence of HSC70-1 gene was 1 953 bp, encoding 650 amino acids. Its complete sequence was 3 390 bp in length, consisting of 8 exons and 7 introns. We screened four SNPs (at 821, 1 105, 1 200 and 2 804 bp on the introns) by direct sequencing, and found that the individuals with CC genotype of C-821G site had significantly higher values of body mass or total length than those with CG or GG genotypes (P<0.05). At the position of A-2804T, the individuals with TT genotype had significantly higher values of body mass or total length than those with AT or AA genotypes (P<0.05). The other two SNP loci were not significantly correlated with growth traits (P>0.05). The optical combined genotype of HSC70-1 gene was D1 (CC--CCTT), which had significantly higher values of body height or total length than those with D5. The growth-related C-821G, A-2804T and D1 can be useful candidate molecular markers for largemouth bass molecular marker-assisted selection.