Research On The Genetic Effects And Expression Analysis Of FSHβ And FSHR Genes In Jinghai Yellow Chicken

Traditional breeding method has made great improvement in many economically important traits in poultry industry, yet it has consume a large amount of time and money. Since the last few decades, molecular biology technique has been generally applied in poultry breeding. Candidate gene approach is a more common approach to finding quantitative trait locus (quantitative trait locus, QTL) on genes related to economic traits’variation. As important economic traits, body weight and reproductive traits were controlled by complex genetic factors. Therefore, revealing the molecular mechanism of the growth and upgrowth of poultry have a lot of benifits of chosing important traits. In this study, PCR-SSCP technique was used to detecte the single nucleotide polymorphism of FSH (follicle-stimulating hormone, FSH) β-subunit gene and its receptor (follicle-stimulating hormone receptor, FSHR) gene in Jinghai yellow chicken, and analysis the relationships of SNPs and production traits; In addition, RQ-PCR method has been used to study the expression of FSHβ gene and FSHR gene in Jinghai yellow chicken, studied the expression at different growth stages and in different tissues. The results shows:1. All exons of FSH(3 gene were detected, four mutations were all located in exon 3, the adjacent mutations C2049T and A2050T showing AA, AB and BB 3 genotypes; T2341C mutation, showing CC, CD and DD 3 genotypes; A2467C mutation showing EE, EF and FF 3 genotypes. The result indicates that:12-week-old chickens weight AB-type were significantly higher than BB-type (P<0.05), EF-type were significantly higher than that of EE-type (P<0.05); 2-week-old chickens weight CC-type chickens was significantly higher than CD-type chickens (P<0.01), however, the mutations above have no significant influence on reproductive traits. Thus, AB-type, CC-type and EF-type are dominant genes on growth traits, we could be initially inferred FSHβ gene was closely related to the growth of chickens.2. FSHR gene has been detected the polymorphisms on exon 1 and 10. The results showed that FSHR gene mutation on exon 1 C159T forming three genotypes namely AA, AB and BB; FSHR gene point mutation C75429T on exon 10 forming three genotypes CC, CD and DD. By the correlation analysis we could found that 2-week-old chickens weight AB-type was significantly higher than BB genotype (P<0.01), AA-type significantly higher than BB-type (P <0.05); 6-week-old chickens weight AA and AB type were significantly higher than BB type (P <0.05), CD type chickens were significantly higher than CC genotype (P<0.05); the age at first egg CC genotype and CD type were significantly earlier than DD type (P<0.05); 300 days egg number AB type was significantly higher than AA type chickens (P<0.05). These SNPs have no significant influence on the rest traits.3. FSHβ gene gene expression pattern in different growth stages and tissues in Jinghai yellow chicken were studied. We could found the highest levels of gene expression of FSHP gene are in the pituitary and gonad, at 0-20 weeks of age, FSHβ gene mRNA abundance in 20 weeks, the trend of FSHP gene expression in males and females are the same, in pituitary when the chicken at birth the relative expression of FSHβ gene is almost zero, to 4-week-old with a small margin on the rise, from 4 weeks to 16 weeks the expression have a great rise; hen increased to the maximum at 20-week-old, that is to say:from 4 weeks to 20 weeks FSHP gene expression in the hen’s skyrocketed; from 4 weeks to 16 weeks on the cock FSHβ gene expression is also linearly rise. In the ovary when the chicken at birth a small amount of FSHP gene expression, after 4 weeks old then to minimize stabilized. In addition,4 weeks and 16 weeks FSHP gene expression in hens higher than cock.4. FSHR gene gene expression pattern in different growth stages and tissues in Jinghai yellow chicken were studied. FSHR gene was expressed highest in gonad, its expression was highest at birth. At 0-20 weeks of age, FSHR gene expression in the ovary and testis decreases with the growth of age, the trend has decreased in 4 weeks and 16 weeks respectively,20 weeks hens ovaries FSHR gene expression compared with 16 weeks was a slight rise. FSHR gene expressed slowly steady rise in the cock small amplitude in the pituitary, relatively speaking, hen and cock FSHR gene expression levels similar in the same period, the expression of hen’s ovary slightly higher than cock’s testicles.