There are several changes in the morphological features and functions of an ageing individual some of which are reduction in muscle and bone mass, decline in cognitive and memory functions, decline in sensory perceptions, decline in sexual activity and an increased propensity to develop chronic conditions, like cancer.
Several of these diseases can be traced to
specific genes. And those who are free of diseases, despite their advanced years, can attribute their freedom to ‘disease-protective’ genes. It is indeed ironical that the same gene, in different forms, can be beneficial or hinder the well being of an individual.

Some of the common, age-related diseases are briefly discussed in this article.