Study of genetic polymorphism in BMPRIB gene and its association with improving twin production in Egyptian sheep and goats

摘要

The present research was carried out to investigate the genetic polymorphism in BMPRIB (FecB) gene and to test whether this polymorphism is associated with improving twin production in Egyptian domestic sheep and goats. Blood samples were collected from 139 animals including 95 of sheep and 44 of goats. These animals involved 113 mothers (83 of sheep and 30 of goats) at the first, second, third and fourth parity. The other remaining 26 females (12 of sheep and 14 of goats) were at sexual maturity age to detect and select the females that carry desirable gene markers for their using in successful breeding program. Genomic DNA was extracted from whole blood samples. PCR was carried out for amplification of a fragment with 140 bp of FecB locus. PCR-RFLP, PCR-SSCP and nucleotide sequence analysis were performed to detect and identify the genetic polymorphism of the candidate gene. Results of PCR-RFLP analysis observed no genetic polymorphism in FecB locus. However, PCR-SSCP analysis clarified genetic polymorphism with two patterns (P1 and P2) in sheep. Pattern 1 was detected in 12 animals including 11 mothers and one female at age of sexual maturity. Pattern 2 was observed in 83 animals involving 72 mothers and 11 females at age of sexual maturity. All goat animals were monomorphic and they were identical with P2 of sheep. The mothers with P1 had more percentage of twin production and increase the mean number of lambing than mothers with P2 and statistical analysis showed that there were significant differences between the two patterns. Sequence analysis determined two types of alleles, mutant allele A and wild type allele T with two genotypes AT and TT. Genotype AT was noted to be associated with improving twin production and increase the mean number of lambing in comparison with TT genotype. In conclusion, the present research clarified that polymorphism in FecB locus of BMPRIB gene is a favorable genetic marker that influences the fecundity of Egyptian small ruminant especially in sheep.