Polymorphism of 3′ Untranslated Region in GRIN1 Gene and Its Correlation with Eggshell Quality in Changshun Green-shell Layer

Purpose To explore the effects of polymorphism of 3′ untranslated region (UTR) in GRIN1 gene on eggshell quality in Changshun green-shell layer.

Methods A total of 185 healthy layers were selected for egg production at 45 weeks of age. Egg weight, egg shape index, eggshell strength, eggshell thickness and eggshell weight were measured. Primers were designed by NCBI and PrimerPremier 3.0. SNPs in the 3′ UTR region of GRIN1 gene were screened by forward sequencing.

Results Four SNPs, including g.30871C>T, g.31017A>G, g.31158A>C and g.31166G>C, were detected in the 3′ UTR region of GRIN1 gene, but only g.31158A>C and g.31166G>C showed strong linkage disequilibrium, and g.30871C>T and g.31017A>G deviated significantly from Hardy-Weinberg equilibrium. In the association analysis between g.31017A>G and eggshell quality, the egg weight of genotype GG was significantly higher than that of genotype AA (P<0.05). Five haplotypes (H1, H2, H3, H4, H5) and eight diplotypes (H1H1, H1H2, H1H3, H2H2, H2H3, H2H4, H3H5, H4H4) were produced by four SNP loci. The egg weight of diplotype H3H5 was significantly higher than that of diplotype H2H2 and H2H3 (P<0.05), and the eggshell weight of diplotype H3H5 was significantly higher than that of diplotype H2H2 (P<0.05), but there were no significant differences among indexes of other diplotypes (P>0.05).

Conclusion GRIN1 gene in Changshun green-shell layer is significantly correlated with eggshell quality, and g.31017A>G has significant effect on eggshell quality, which can be used as a reference for improving eggshell quality.