Genetic polymorphism of bone morphogenetic protein receptor 1B (BMPR-1B) gene and its association with litter size in Indonesian fat-tailed sheep
The Indonesian fat-tailed sheep (IFTS) is a local sheep that has been long time raised and well adapted to the extreme environments of Lombok Island. The present study was conducted to determine the polymorphism of bone morphogenetic protein receptor 1B (BMPR-1B) gene and its association with litter size in the IFTS breed by employing forced polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods in the IFTS. Polymorphism of BMPR-1B genes on IFTS population were identified by the forced PCR-RFLP methods. The result of this study showed that mutation of BMPR-1B gene resulted in two allele of wild type (+) and mutan allele (B) with frequencies of 0.807 and 0.193, respectively and three genotype of BB (110 bp/110 bp), B+ (110 bp/140 bp), and ++ (140 bp/140 bp) with almost unequal frequencies distribution of 0.060, 0.268, and 0.672. Genetic diversity of BMPR-1B genes caused different litter sizes on individual IFTS. A highly significant difference (P<0.01) was observed in the average of litter size in different genotypes. The highest average of litter size was found in the genotype of BB, that is, 1.685 lambs.
Keywords: Bone morphogenetic protein receptor 1B (BMPR-1B), gene, mutation, polymorphism, litter size