Molecular diagnosis and control strategies for the relevant genetic diseases of cattle
Abstract
The availability of the bovine genome sequence and the use of DNA markers have widened our understanding of a number of hereditary diseases in cattle, leading to the development of techniques for their early diagnosis. By isolating DNA from nucleated cell samples, followed by in vitro amplification techniques and digestion with restriction enzymes, it is now possible to detect the presence of lethal or mutant alleles for a specific phenotype. Such techniques are already being used for the study of genetic diseases of dairy cattle such as BLAD (Bovine leukocyte adhesion deficiency), CVM (Complex vertebral malformation), DUMPS (Deficiency of uridine-monophosphate synthase) and citrullinemia, among others, where the disorder is caused by the presence of a recessive allele in homozygosis. Although the frequency of these alleles in the population is usually very low, it can be easily increased if heterozygotic (carrier) sires are used during large-scale stockbreeding, ultimately resulting in significant economic losses; on the other hand, certifying the absence of such mutations in sires increases their value. Since there is a worldwide tendency towards the implementation of monitoring programs for hereditary diseases in cattle, it is important to update the technical personnel involved in cattle breeding (researchers and veterinary doctors) as well as farmers on the use and importance of DNA molecular markers in animal health.
