Sequencing-based polymorphism in leptin receptor gene and lack of association with postpartum anestrus in Murrah buffaloes

In order to detect polymorphism in exon 20 of the leptin receptor (LEPR) gene and its possible association with postpartum anestrus (PPA), peripheral blood samples were obtained from 40 Murrah buffaloes including 20 PPA (>120 days after parturition) and 20 normal cyclic (<60 days after parturition) buffaloes having similar postpartum estrous conditions over previous consecutive gestations. Genomic DNA was isolated, and PCR was standardized to amplify partial exon 20 of the LEPR gene of 413 bp. Amplified fragments of the gene were sequenced and sequence variation was detected by assessing multiple alignments. The LEPR gene showed polymorphism at A231G, C247A, and G347A. Chi-square test of these 3 polymorphism sites between the 2 groups did not reveal any significant association of polymorphism with PPA. Hence, polymorphism at exon 20 of the LEPR gene was found in Murrah buffaloes, but the role of these polymorphisms in PPA could not be established.