Association of gene polymorphisms of estrogen receptor, follicle-stimulating hormone β and leptin with follicular cysts in Large White sows

- Finding ESR/PvuII polymorphisms are highly associated with follicular cysts and that sows ESR/PvuII genotype have lower rate of suffering from cysts (P = 0.021).
- Finding the haplotypes EBCM and EBTM within estrogen receptor, follicle-stimulating hormone β and leptin had significant dominance effect on follicular cysts (P < 0.05).
- Our findings positively improve the development of biological biomarkers, which is thereby profitable in breeding programs and ovary-protective therapy of reproductive disease in pigs.

Ovarian follicular cysts are one of leading causes of infertility and financial loss in pig breeding program. This study was carried out to investigate the association between polymorphisms of estrogen receptor (ESR), follicle-stimulating hormone (FSH) β, and leptin genes and follicular cysts in sows. A total of 47 and 120 sows with follicular cysts and normal follicles, respectively, were selected to evaluate whether these candidate loci affect the formation of follicular cysts in sows. The polymorphisms of ESR, FSHβ, FSHβ/HaeIII and leptin genes were tested by PCR and PCR-RFLP methods. Cyst-normal case data analysis showed that ESR/PvuII polymorphisms are highly associated with follicular cysts and that sows ESR/PvuII genotype have lower rate of suffering from cysts (P = 0.021). Unfortunately, FSHβ, FSHβ/HaeIII, and leptin C3469T polymorphisms were found no significant difference in follicular cysts sows and normal sows. These results suggest that FSHβ, FSHβ/HaeIII, and leptin C3469T genotypes are not able to effect the presence of follicular cysts (P > 0.05). In addition, the haplotype EBCM and EBTM within four loci of genes had significant dominance effect on follicular cysts (P < 0.05). The detection of ESR/PvuII polymorphisms and haplotype EBCM and EBTM can positively improve the development of biological biomarkers, which is thereby beneficial in breeding and ovary-protective therapy of reproductive disease in pigs.