Single Nucleotide Polymorphisms In Geese ESRα Gene And Its Association With Egg Production

The estrogen receptor(ESR) is a member of the nuclear receptor superfamily, including three subunits,estrogen receptor alpha(ESRα),beta(ESRβ) and ESRγ.ESR is a ligand-activated transcription factor containing several biding site in animals.ESR influences the expression and regulation of estrogen gene in the tissues,and therefore, affects the development of follicle in the reproduction cycle of female vertebrate.In this study,ESRαgene was selected as a candidate to screen the genomic variation. The Wanxi-White geese(n=200),a Chinese local breed,and Rhine(n=80) were used to detect SNPs in the ESRαsubunit gene by PCR-SSCP,and the association of ESRαgene polymorphisms with egg production traits was analyzed.By genome comparison,4 pair of primers were designed using Primer Premier5.0 and DNAstar programme based on the sequence of chicken ESRαgene(GenBank accession no.NC006090) to obtain DNA fragments covering the exon1 and exon4 of geese ESRαby PCR.The exon1 and exon4 of Wanxi-White geese and Rhine geese was cloned(GenBank accession number:EU266072,EU417675) by the method of Genomic comparison. Homological analysis suggested that the homology of Wanxi-White geese ESRαexon1 with Rhine and chickens exon1 was 99%,and 95%.And the homology of Wanxi-White geese ESRαexon4 with Rhine and chickens exon4 was 100%,and 96%.The SSCP detection results showed that no polymorphism site was found at exon4 locus of ESRαgene and a SNP was detected at exon1 by F1b prime.Sequencing of this fragment revealed an A→G transition in Wanxi-White geese.Allele A and B were tested in exon1,and AA,AB and BB genotypes were found,the genotypic frequencies of which were 0.190,0.585 and 0.225,respectively.The frequency of allele A and B were 0.482 and 0.518 respectively.x~2 test suggested that the population were in the state of Hardy-Weinberg equilibrium at the sites.Polymorphic information content(PIC) of polymorphic sites in Wanxi-White geese population detected by F1b primer was 0.3747 respectively.Association analysis of egg production traits and ESRαgene polymorphisms in Wanxi-White geese showed that SNP in exon1 did not influence egg production traits.