Ageing is a normal process in all living organisms including human. With the progress of ageing physiological functions of different organs of the body become slower leading to many age-related diseases that are responsible for shortening of longevity. But this reduction of ageing varies from individual to individual. This diversity of changes in ageing process has come to the mind of scientists to find out some factors that regulate ageing both at the cellular and genetic levels. All these improvements may be due to the advancement of medical research as well as the development of new drugs in relation to different types of diseases starting from infant mortality to age related ailments. Still demographic data of increase in longevity in different countries have opened new ideas to the scientists that the identification of factors or genes that regulate ageing is urgently needed. Demographic studies show that human life span has no sign of fixed limit imposed by biology or other factors. It has been noted that both the average and maximum life span have increased steadily over time for more than a century. Thus the research on Ageing , its genetics and the application of modern technique of Genetic engineering and other methods to reverse the ageing has gained its importance to enjoy healthy and active life even in old ages.
