THE IMPORTANCE OF CLINICAL GENETICS (Part I)

Recent developments in molecular and human genetics have increased interest in genetics. Clinical genetics is involved in the diagnosis, management, and control of hereditary disorders and has emerged as an important discipline in small animal practice for several reasons. Effective preventative measures reduced the frequency of infections, nutritional disturbances, and intoxications. Furthermore, life-saving advances in medicine and surgery have increased the chance of survival of companion animals and thus tend to raise the recognition of genetic defects. Inbreeding practices to preserve the desirable traits in certain breeds favor the occurrence of recessively inherited diseases. Technologic advances have allowed the recognition and characterization of the clinicopathologic, biochemical, and molecular basis of many hereditary diseases. Whereas in the past genetics had a large role of a few patients, specific genetic information is becoming critical in small animal practice for every patient. The many specific genetic disorders are covered under individual organ systems. This article on clinical genetics reviews the characteristic clinical features of hereditary diseases in small animals, the various modes of inheritance, diagnostic tests, and management and control of these diseases. The importance of genetic counseling is addressed, i.e., providing information for pet owners and breeders of animal afflicted with a hereditary disorder concerning the consequences of such a disorder and the ways in which it can be prevented in future generations. Furthermore, the recent completion of the human genome sequence and initiatives for a canine and feline sequence and availability of a partial canine genome sequence have greatly facilitated the research of single gene and complex inherited diseases. The recently introduced field of genomics is the study not just of single genes, but of the organization, functions, and interactions of all genes in the genome, including their interaction with environmental factors.