Novel Mutation Site in HOXD1 and RXFP2 Genes Detected in a Polycerated Garut Sheep (Ovis aries)

Garut sheep (Ovis aries) is one of Indonesian native sheep breeds from West Java which is bred for meat production purposes. Despite this, Garut rams with good horn characteristic are also used for the fighting contest festival which is the famous cultural tradition in West Java. This study was aimed to detect the mutation site in the two functional genes controlling horn development i.e. HOXD1 and RXFP2. In this study, a rare polycerated (4 horns) Garut sheep was found at Cipacing Village, Sumedang Regency of West Java and used for investigation and compared with nine wildtype (2 horns) Garut sheep. Therefore, the partial sequences of HOXD1 (788 bp) and RXFP2 (505 bp) genes were amplified for the forward sequencing analysis. Results showed a presence of two novel mutations in the tested Garut sheep, namely g.742_743indel. TAAG in the HOXD1 gene and g.2218A>T in the RXFP2 gene. Specifically, a polycerated Garut sheep had the deletion 4 bp allele in HOXD1 gene and T allele of RXFP2 gene. In conclusion, horn characteristics of Garut sheep were controlled by novel mutation site in HOXD1 and RXFP2 genes.