马氏珠母贝肌肉生长抑制素基因eSNP多态性与生长性状的关联分析

Single nucleotide polymorphisms of myostatin gene and its association with growth traits in the pearl oyster, Pinctada fucata

肌肉生长抑制素myostatin（MSTN）,是目前已知抑制肌肉生长最强效的分化因子,具有负向调控肌肉生长、发育的作用,它与生长之间的这种单向作用关系,使其在养殖生物遗传改良上具有重要的潜在应用价值。文以马氏珠母贝MSTN基因21个e SNP位点作为候选SNP位点,对106只马氏珠母贝进行基因分型并与8个生长性状进行关联分析。SNP最小等位基因频率的范围为0.028 3～0.490 4,多态信息含量（PIC）的范围为0.093 6～0.375 0,观测杂合度（Ho）及期望杂合度（He）的范围分别为0.028 3～1.000 0及0.098 9～0.502 7。2个SNP位点与生长性状显著关联：g.3154 A〉G位点的GG型个体的壳高、壳长、总重、壳重、软体部重和闭壳肌重显著大于AG型个体（P〈0.05）;g.4379A〉G位点GG型个体的壳高、壳长、铰合线长、总重、软体部重和闭壳肌重显著大于AG型个体（P〈0.05）。g.3154 A〉G位点和g.4379A〉G位点间无显著交互作用。这2个SNP可作为潜在的马氏珠母贝基因型选择育种标记。

Myostatin（MSTN）, known as the most powerful growth differentiation factor, plays a crucial role in the negative regulation of muscle growth and development. The existence of a single gene with such a major effect on the muscle growth makes it have the potential value in the genetic improvement of animals. In this study, we used 21 e SNPs from myostatin gene to divide the genotypes of 106 individuals from a breeding stock of pearl oyster Pinctada fucata and made the correlation analysis with the eight growth traits. The results show that the minor allele frequency（MAF） and polymorphism information content（PIC） are in the range of 0.028 3 to 0.490 4 and 0.093 6 to 0.375 0, and the observed and expected heterozygosities range from 0.028 3 to 1.000 and 0.098 9 to 0.502 7, respectively. Two SNPs are significantly associated with growth traits ：for the g.3154A〉G site, individuals with GG type are significantly greater than those with AG type in the shell height, shell length, total weight, shell weight, soft tissue weight and adductor muscle weight（ P〈0.05）; for the g.4379A〉G site, ones with GG type are significantly greater than those with AG type in the shell height, shell length, hinge line length, total weight, soft tissue weight and adductor muscle weight（ P 〈0.05）. There is no significant interaction between g.3154 A〉 G site and g.4379A〉G site. These two SNPs could be used as the potential molecular markers in the genotype-selective breeding for P.fucata.