Abstract

The understanding of gene function and its relevance to human disease is one of the most important objectives in the postgenome era. The most direct avenue to uncovering this relationship is the positional cloning of human disease genes, particularly for disorders with Mendelian inheritance. Even when multiple mutational mechanisms result in the same disorder, affected individuals from different families can be ascertained, to find those individuals with specific mutations on a single gene. This provides solid evidence that mutation of a gene is causative of the disease and gives important information regarding gene function.