Improving Muscle Inosine Monophosphate (IMP) Contents in Wenchang Chicken by Pyramiding Favorable Genotypes of ADSL and GARS-AIRS-GART Genes

摘要

This study was designed to improve muscle Inosine Monophosphate (IMP) contents in Wenchang chicken by pyramiding favorable genotypes of the Adenylosuccinatelyase (ADSL) gene and Glycinamide Ribonucleotide Synthetase-Aminoimidazole Ribonucleotide Synthetase-Glycinamide Ribonucleotide Transformylase (GARS-AIRS-GART) gene. PCR-SSCP method and DNA sequencing were used to identify the Single Nucleotide Polymorphisms (SNPs) in exon 2 of ADSL gene and 5?-flanking of GARS-AIRS-GART gene. Association between the detected SNPs and different pyramiding genotypes with IMP contents were tested by least square analysis. The early growth and production performance of individuals with different pyramiding genotypes were also compared. The results showed two SNPs were detected, C/T substitution at position 3484 in exon 2 of ADSL gene and T/C substitution at position -179 in 5?-flanking of GARS-AIRS-GART gene, each had three kinds of genotypes (TT, CT, CC). The association analysis indicated the two SNPs had significant correlation with IMP contents (p<0.05), there were higher (p<0.05) IMP contents in birds that were TT genotype than those of CC and CT genotypes for both ADSL and GARS-AIRS-GART genes and the additive effects of the favorable TT genotypes on IMP contents were respectively 0.248 and 0.227 mg -1 g. After gene pyramiding, the association analysis showed birds with pyramiding TTTT genotype had higher IMP contents (2.720 mg g-1, p<0.05) than those with other pyramiding genotypes. This value was increased by 10.34 and 13.23% compared to the IMP contents of single genotype TT for ADSL and GARS-AIRS-GART genes. Factor test also showed the two favorable TT genotypes played significant role (p<0.05) on IMP contents in pyramiding genotype, however, their interaction effect was not significant (p>0.05). The average 90 days old weight, age at first egg and 72 weeks old laying performance in different pyramiding genotype populations had no difference (p>0.05). The muscle IMP contents of Wenchang chicken can be markedly improved by pyramiding favorable genotypes of ADSL and GARS-AIRS-GART genes and still maintain the original production performance.