ABCA4 and diabetes mellitus: One of the seven regions was identified on chromosome 2 in ITU cluster A and contains two genes: G6PC2, a pancreatic glucose-6-phosphatase implicated in the modulation of fasting plasma glucose levels [227] that is a major target of cell-mediated autoimmunity in diabetes [228], and the ATP-binding cassette transporter gene ABCB11, mutations in which cause autosomal recessive progressive familial intrahepatic cholestasis [229, 230].