Phenotypes

In a conference abstract, Haton et al. (2000) reported that, by cloning and sequencing a very likely comparative candidate gene (based on the homologous human disorder), they had identified a 76-bp insertion in exon 12 of the Factor XI gene as being causative of Factor XI deficiency in Holstein cattle. This discovery was fully described by Marron et al. (2004) who explained that "This insertion introduces a stop codon that results in a mature ...

See also: 'OMIA:001009-9915 : Hemimelia, tibial in Bos indicus'

Syndactyly has been reported in many breeds of cattle in many countries. Most of the documentation, however, concerns its occurrence in US Holsteins, where, as a result of the siring of more than 60,000 calves by a bull who was subsequently shown to be a carrier, the disorder attracted considerable attention (Anon., 1967). The possibility that artificial selection favouring heterozygotes may have contributed to the unacceptably high frequency ...