Analysis of HSP70 in Litopenaeus vannamei and detection of SNPS

Abstract

The Hsp70 gene plays an important role in the animal immune response. In order to analyze the linkage between the genetic polymorphisms of Hsp70 and the virus-resistance trait of the shrimp, we detected SNPs in the coding region of Hsp70 by direct sequencing in 104 specimens of Litopenaeus vannamei from three shrimp populations (one TSV-resistance line and two TSV-susceptibility lines). Five SNPs were found including 661C/A, 7121/C, 782C/T, 892C/T, and 1090C/T in the fragment of Hsp70 (GenBank accession no. AY645906). There were significant difference of the allelic frequency of SNP 892C/T polymorphism between the TSV-resistance population and the two TSV-susceptibility populations (P < 0.001). A TSV-challenged test was performed to divide the shrimps into TSV-resistance group and TSV-susceptibility group. The 892C/T SNP genotypes of each shrimp sample were detected by pyro-sequencing. The allelic frequency of SNP 892C/T were significant difference between TSV-resistance group and TSV-susceptibility group (P < 0.001). The results show that the genetic polymorphisms of Hsp70 are likely associated with virus-resistance trait in populations of L. vannamei.