Genetic analysis of congenital hypotrichosis with anodontia in cattle

In three male German Holstein calves, black and white spotted, congenital h ypotrichosis and nearly complete anodontia was observed. The pedigree of th e probands being maternal halfsibs and grandmaternal grandsons supports a m onogenic, X-linked recessive inheritance. Chromosomal Xq-deletions were not detected. similar congenital anomalies are known in tabby mice and in huma ns as anhidrotic ectodermal dysplasia (ED1, EDA). The human gene causative for ED1 and the Tabby gene are located on the X-chromosome. Therefore, the moleculargenetic marker analysis in our material was restricted on the X-ch romosome. Using identical by descend mapping based on 20 microsatellites, w e were able to identify an exclusively joint genomic region on the long arm of the X-chromosome among the affected calves. The putative location of th e gene locus for congenital hypotrichosis with anodontia maps into the regi on of the marker BM4604 on position 76.5 cM of the X-chromosome.