Polymorphism And Expression Of FSHR And Its Relations With Litter Size In Swine

Reproductive traits is one of the important economic traits in pigs,and Sow reproductive capacity is controlled by Hypothalamic-pituitary-ovarian axis.FSH is a glycoprotein hormone secreted by the anterior pituitary.FSH direct effect on ovarian regulation of animal breeding activity by FSHR.Many studies suggest an association between animal FSHR gene polymorphism and its fertility.This study focused on the following three aspects:Using PCR-SSCP and direct sequencing to analyze the polymorphisms in exon 10 of FSHR gene and the relationship between polymorphisms and Sow reproductive capacity in three pig breeds including Berkshire,Wannan Black and two-way crossbred pigs produced from Berkshire ? and Wannan Black pig ?.Using RT-PCR to comparing the gene expression level of transcription of different genotypes in Wannan Black,and the gene including FSHR gene in ovaries and FSH-? gene and GnRHR gene in pituitary.Using ELISA to measure and analyze the hormones level in blood of different genotypes in Wannan Black,and the hormones including FSH estradiol and progesterone.The results are as follows:Three SNPs(C1491T,G1885 A and C1977T)were demonstrated in exon 10 of porcine FSHR gene,and three genotypes(AA,AB and BB)about C1491 T and two haplotypes(D and E)about G1885 A and C1977 T were identified.A further analysis of SNP genotypes associated with reproductive traits including total number born(TNB)and number born alive(NBA)was carried out in three pig populations including Berkshire,Wannan Black and two-way crossbred pigs produced from Berkshire ? and Wannan black pig ?.The results showed that the TNB and NBA of Wannan Black pigs with an AB genotype were significantly higher than AA genotype sows(P < 0.01)in multiparity sows and all parities.The TNB and NBA from Berkshire pigs with a DE genotype were significantly higher than DD and EE genotype sows(P < 0.01)in gilts sows and all parities.The overall trend of TNB and NBA from the three identified genotypes was DE>DD>EE.The results showed that polymorphisms of exon 10 of the FSHR gene had a significant effect on litter size traits of Wannan Black and Berkshire pigs.The FSHR gene espression level in ovaries with an AB genotype were significantly higher than AA genotype sows(P < 0.05).The FSH-? gene espression level in pituitary there was no significant difference between AA genotype and AB genotype.GnRHR gene espression level in pituitary with an AB genotype were significantly higher than AA genotype sows(P < 0.05).The estradiol concentration in blood with an AB genotype were significantly higher than AA genotype sows(P < 0.05).The progesterone concentration in blood with an AA genotype were highly significantly higher than AB genotype sows(P < 0.01).The FSH concentration in blood there was no significant difference between AA genotype and AB genotype.The results showed there are polymorphisms of exon 10 of the FSHR gene,and the polymorphisms had a significant effect on litter size traits;There is a difference between different genotypes pig in the FSHR gene espression level in ovaries and GnRHR gene espression level in pituitary,and in the blood concentrations of estradiol and progesterone.The results suggest that the polymorphisms of FSHR may affect the FSHR gene espression level in ovaries and the level of estradiol and progesterone in the blood,and it becomes one of the main causes of differences in reproductive capacity bewteen different genotype.