Chromosomal assignment of the ovine hairless (hr) gene by fluorescence in situ hybridization

Congenital hypotrichosis in mammalian species consists of partial or complete absence of a hair coat at birth. Affected individuals having a partial hair coat at birth may loose it subsequently. In humans, mice, and rats, the hairless (hr) gene is often responsible for this disorder and is highly homologous suggesting high conservation among mammals. The hr gene codes for a protein which is a transcriptional co-repressor for thyroid hormone receptors. More recently, hypotrichosis was described in Sicilian dairy sheep belonging to the Valle del Belice breed. Because the hypotrichotic phenotype is an undesirable defect for farmers, affected lambs are slaughtered soon after birth. Therefore information on the population frequency of the disorder is missing. The hr gene was chosen as a functional candidate gene for the hypotrichotic disorder in the Valle del Belice dairy sheep. The aim of this paper was to physically map the ovine hr gene using fluorescence in situ hybridization (FISH). The chromosomal assignment for the ovine hr gene was OAR 2p21-22.