ASSOCIATION BETWEEN POLYMORPHISMS OF LHR AND INHIB β A GENES AND FERTILITY TRAITS IN EGYPTIAN BUFFALO HEIFERS

Abstract

The objectives of this study were to detect polymorphisms of LHR and INHIBβA genes and their association with reproductive problems (repeat breeder syndrome) among Egyptian buffalo heifers using PCR–RFLP and DNA sequencing techniques. DNA was collected from 243 (96 normal fertile and 147 repeat breeders) Egyptian buffaloes. PCR-HhaI of 303 bp from LHR gene revealed one uncut TT band confirmed by DNA sequencing showing no SNPs in all the enrolled animals. Meanwhile PCR-StyI of 288 bp from INHIBβA gene yielded two digested (150 and 138 bp) fragments for genotype CC, three fragments (288, 150, 138 bp) for genotype CT and one undigested fragment (288 bp) for TT genotype. Results indicated that out of 96 normal fertile animals, the frequencies of CC, CT and TT genotypes were 32.3%, 39.6% and 28.1% respectively. Meanwhile 15%, 38% and 47% respectively in repeat breeder buffaloes. Frequencies of C and T alleles were 52% and 48% in normal animals and 34% and 66% in repeat breeders. Statistical analysis indicated that there was a significant association between occurance of repeat breeder and INHIBβA genotypes. DNA sequencing declared C/T SNP in intron 1 of INHIBβA gene that significantly appeared with higher frequency in repeat breeder than normal fertile helfers indicating that T allele is a risk factor and can be used in MAS for early selection of repeat breeder heifers, so improving reproductivity of Egyptian buffaloes.