Cellular Aging: DNA Polymorphisms - Potential Significance
Whether studies of the effect of DNA polymorphisms in genes involved in the replication and repair of DNA lead to significant new insights into the causes of aging will not be known until such studies have been completed. The potential significance is high, however. A convincing demonstration that genes involved in DNA replication and repair effect the life span and the phenotype of aging would provide strong support for the hypothesis that mutations in somatic cells contribute to the aging process.
Will these studies be of importance in other areas of biomedical research? The answer to this question is most certainly "yes." All aspects of DNA metabolism are essential for the survival of virtually all organisms. The identification, mapping, and functional studies of polymorphic loci will provide important new information about the mechanisms of DNA replication and repair. At a more applied level, these studies will almost certainly increase our understanding of many diseases, including cancer. It is now generally accepted that this disease is caused by gene mutations in somatic cells, and studies of the nature and extent of variation in genes involved in DNA repair and replication will be a very important area of cancer research.
Whether studies of genetic variation in aging will have practical applications is, again, dependent on the outcome of research in this area. An obvious possibility is that information derived from these studies will permit the identification of individuals who are at increased risk for the development for specific age-related conditions and diseases. Such developments would raise some ethical concerns, mainly concerning the potential for discrimination. On the other hand, with the development of effective therapies and preventive programs, the ability to accurately predict the risk of developing specific diseases years, or even decades, in advance of their onset would be of immense practical value in the treatment of elderly patients.
THOMAS H. NORWOOD
See also ACCELERATED AGING: HUMAN PROGEROID SYNDROMES; ALZHEIMER'S DISEASE; CANCER, BIOLOGY; CELLULAR AGING: TELOMERES; DNA DAMAGE AND REPAIR; GENETICS: GENE EXPRESSIONS; GENETICS: GENE-ENVIRONMENT INTERACTION; STRESS.
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