Study Of BMPR-IB Gene As Candidate Gene For Prolificacy In Hu Sheep And Optimization Of Molecular Detection Methods For It

Hu sheep is famous for its hyper-Prolificacy in the world. The Fec B(Fec = Fecundity, B = Booroola)mutation plays a vital role in increasing ovulation rate and prolificacy in ewes. The effect of the Booroola gene has been shown to be due to a mutation(A746G) in the bone morphogenetic protein 1B receptor(BMPR-1B) that is expressed in oocytes and granulosa cells and is located on chromosome 6. In order to investigate the mechanism of high Fecundity in Hu sheep, the single nucleotide polymorphism(SNP) and copy number variation(CNV) of BMPR-IB gene were investigated by PCR-RFLP and real-time PCR,respectively. Our data show the association of BMPR-IB gene and prolificacy in Hu sheep and provide the reference for understanding the molecular mechanism of hyper-prolificacy in Hu sheep.Our research mainly focuses on two aspects: one was to investigate the association of BMPR-IB gene and prolificacy in Hu sheep, the other was to optimize the detection method of FecB gene for agriculture extension service. The main findings of this study were as follows:1. In this study,blood samples were collected from 51 Hu ewes, and DNA was extracted from these blood. Then the single nucleotide polymorphism of BMPR-IB gene(bone morphogenetic protein receptor type IB) was analyzed using PCR-RFLP in these Hu sheep. Finally, combining with breeding notes of these ewes, the relationship between mutation in BMPR-IB gene and multiplets of these sheep was discovered.FecB(mutation in BMPR-IB) was highly homozygous in Hu sheep,and frequency of it was 90%. All prolific sheep were homozygous mutations and wild type is not discovered in this group. The FecB gene was conducive to early selection in Hu sheep.2. The copy number variation(CNV) of BMPR-IB gene was analyzed using Q-PCR in these Hu sheep,and basic transcription factor3(BTF3) was selected as internal reference gene. Then combining with breeding notes of these ewes, the relationship between CNV of BMPR-IB gene and multiplets of these sheep was discovered. The CNV of BMPR-IB gene existed in these Hu sheep, but it wasn’t associated with litter size in Hu sheep. Low of CNV of Fec B gene wasn’t inexistent in sheep that average litter size is greater than three.3. Blood and hair samples were collected from 38 Hu ewes. DNA was extracted from these blood.Hair follicle was made into digestive system using Proteinase K. Then the SNP of BMPR-IB gene was analyzed using PCR-RFLP in DNA of blood and digestive system. Finally, the result of Hair follicle wascompared with the result of blood. The method that hair follicle was made into digestive system using Proteinase K was more quick and easy. It was conducive to agricultural extension.In conclusion, homozygous FecB gene can be used as molecular markers of multiplets. The method that hair follicle was made into digestive system using Proteinase K was more quick and easy. It was conducive to agricultural extension.