Mutations in the exon 10 of prolactin receptor gene change the egg production performance in Wanjiang white goose

To select the molecular genetic markers related to egg performance of Wanjiang white goose, prolactin receptor gene (PRLR) was adopted to be a candidate gene in our study. Five pairs of primers (P1-P5) were designed to detect the SNPs of PRLR gene by PCR-SSCP method. The results revealed that polymorphisms were discovered in the PCR products amplified with P4 primers in PRLR exon 10, three genotypes were found: AA, AB and AC. The sequence of AB genotype is the same as original sequence (DQ660982) in NCBI. There are five mutations in AA genotype: C -> A at 840 bp, C -> T at 862 bp, T -> C at 875 bp, T -> A at 963 bp, A -> T at 989 bp, resulting in amino acid mutations: His -> Asn, Thr -> Ile, Asn -> Lys, Thr -> Ser, and synonymous mutation at 875 bp. Sequencing revealed five mutations in AC genotype: G -> T at 816 bp, A -> T at 861 bp, C -> T at 862 bp, T -> C at 875 bp, A -> G at 948 bp, causing amino acid mutations of Val -> Phe, Thr -> Phe, synonymous mutations at 875 and 963 bp. Besides, there are an N-glycosylation site (NQSR), three casein kinase II phosphorylation sites including SIIE, SKTE, and SLMD in AA genotype; three casein kinase II phosphorylation sites including SIIE, SKTE, and TLMD in AB genotype; three casein kinase II phosphorylation sites including SIFE, SKTE, and TLMD in AC genotype. The annual egg yielding of AB genotype geese are significantly more than those of AA and AC genotype geese on the average (P < 0.05). It is suggested for the first time that PRLR is a promising candidate gene that can affect egg performance in Wanjiang white goose.