For Indians only

one disturbing aspect of the Indian population is the lack of reliable data pertaining to major epidemiological aspects of human disease. Information comes from a western population more likely as not. An example of this is the recent report that environmental influences may be far more significant than genetic ones in the development of a variety of cancers ( Down To Earth , August 15, 2000). The inference follows an examination of birth and death records of twins in three Scandinavian countries. But if one were to inquire whether the relative importance of the two sets of causes is similar in Indians; the information does not exist.

It is, therefore, noteworthy that a study by Quasar Saleem of the Indian Institute of Science, Bangalore and colleagues, focuses on the correlates within the Indian population of a serious hereditary condition or genetic disease ( Human Genetics vol 106, p 179-187).

The condition is actually a family of syndromes known as the autosomal dominant cerebellar ataxias ( adac s). Victims suffer from poor motor co-ordination and speech defects. As the name suggests, the condition results from a dominant genetic mutation.

To date there are at least seven genes that, when mutated, can predispose the appearance of one of the adac s. What makes for a