genetic predisposition

A genetic predisposition is well recognised in both type I
insulin dependent diabetes (IDDM) and type II non-insulin
dependent diabetes (NIDDM). Maturity onset diabetes of the
young (MODY) is a specific form of non-insulin dependent
diabetes that follows autosomal dominant inheritance and has
been shown to be due to mutations in a number of different
genes. Clinical diabetes or impaired glucose tolerance also
occurs in several genetic syndromes, for example,
haemochromatosis, Friedreich ataxia, and Wolfram
syndrome (diabetes mellitus, optic atrophy, diabetes insipidus
and deafness). Only rarely is diabetes caused by the secretion
of an abnormal insulin molecule.