Studies On DNA Molecular Marker Of Candidate Genes Of Egg Quality Traits In Laying Hens

Objective: Egg quality is the important traits in breeding chicken,it has large effect on the efficiency in chicken egg production.So it has been a hot topic for how to improve the egg performance by modern biology technology. In this study, to search for the molecular markers associated with egg quality traits in DNA molecular level and screen out dominant genotypes regulating egg quality traits,furthermore,these dominant genotypes were verified in the offspring(commercial generation).Methods:Using the SSCP methods to detect single nucleotide polymorphisms(SNP) of seven candidate genes(TRPV6,Ca BP-D28 k,CA,OC116,OCX32, OCX36 and OVA) association with eggs quality traits in the parents’ generation of hyline brown hens.Genetic parameters and diversity were also made statistical, and then it is used to study for genetic effect of candidate genes of the egg performance on the traits through association analysis between SNP loci and selected group,screening the preponderant genotype on regulation of egg quality traits, and furthermore,validation and identification advantage genotype in the offspring.The research primarily results as follows:(1) SSCP method was used to detect single nucleotide polymorphisms(SNP) of seven candidate genes(TRPV6,Ca BP-D28 k,CA,OC116,OCX32,OCX36 and OVA).The results showed exon 14 of TRPV6, exon 3 of Ca BP-D28 k, 5 intron of CA,the 1, 5 exon and intron 2 of OC116, 2, 4, 6 exon of OCX32, 3, 4, 5, 6, 7 exon and 4, 7, 8, 12 intron of OCX36, intron 4 and exon 5 of OVA were found polymorphic loci.(2)Correlation analysis among egg quality traits and Calcium transfer protein gene polymorphism results revealed:There were highly significant correlation among AA type of G27314 A mutation of TRPV6 exon 14 and Yolk color(P<0.01) compared AG and GG genotype,respectively.There were superior significant correlation between AG type of A5115 G mutation of Ca BP-D28 K exon 3 and shell strength(P<0.01) than AA and GG genotype.There were highly significant correlation among AA type of G14306 A mutations of CA intron 5 and yolk color(P<0.01) compared AG genotype.(3)Correlation analysis among egg quality traits and matrix protein genes olymorphism results revealed:There were highly significant correlation between AA type of G132 G and G208 A mutations of OC116 exon 1 and egg strength and egg thickness(P<0.01) compared AB and AC genotype. There were very significant correlation between AA type of G2456 G and G2512 A mutations of OC116 exon 5 and egg strength(P<0.01) compared AB and BB genotype.There were superior significant correlation among each type of G4259 T and G4276 C mutations of OCX32 exon 2 and egg strength(P<0.01),respectively.There were very significant correlation between BD type of G6049 G and G6051 A mutations of OCX32 exon 4 and egg weight(P<0.01) compared the other genotype.There were highly significant correlation among each type of G7018 A and G7116 G mutations of OCX32 exon 6 and Yolk weight(P<0.01),respectively.There were superior significant correlation among AA type of G992 A and G1075 T mutations of OCX36 exon 3 and egg thickness(P<0.01) than AB and BB genotype.There were highly significant correlation among each type of G1267 C and G1276 C mutations of OCX36 exon 4 and Haugh Unit(P<0.01) compared the others.There were highly significant correlation among each type of G2472 A mutation of OCX36 exon 5 and egg weight, albumen weight,yolk weight and egg weight(P<0.01),respectively.It was very significant that the correlation between BB type of G2843 A and G2893 G mutations of OCX36 exon 6 and yolk color(P<0.01),compared with the other genotype. There were highly significant correlation among AA type of G3287 G and G3339 G mutations of OCX36 exon 7 and egg weight, albumen weight,yolk weight(P<0.01), compared the other genotype.There were highly significant correlation among CC type of G5118 C and Haugh Unit,albumen height(P<0.01),than the others.There were superior significant correlation among AA type of G4296 C and G4323 A mutations of OVA exon 5 and Haugh Unit,albumen height(P<0.01),than BC and BB genotype.(4)Analysis of the effect of Markers assistant selection(MAS) of gene CABP-D28 K and OCX32.The results showed that AG genotype of gene CABP-D28 K was the dominant one on regulating egg strength, and AA genotype of gene OCX32 was the dominant one on regulating yolk weight.Conclusion: AG genotype of gene CABP-D28 K was the dominant one on regulating egg strength,AA genotype of gene OCX32 was the dominant one on regulating yolk weight.Those results would provide a theoretical basis to improve the egg quality traits by utilizing molecular marker assisted selection technology in future.