MODY3 and Dyslipidemia in Siblings With Clinical Courses before the Diagnosis of Diabetes

Abstract

A 17-year-old boy and his younger sister, a 15-year-old girl, were suspected of having diabetes mellitus based on a positive result according to a urinary glucose test at a school physical examination. They initially had normal findings on the oral glucose tolerance test, but they both developed diabetes mellitus within a few years of the start of the clinical course. They were genetically diagnosed with MODY3 with a c.1298C>T mutation in the hepatocyte nuclear factor-1 alpha (HNF-1α) gene and were simultaneously diagnosed with primary dyslipidemia, exhibiting type IIb or IV manifestation. Their clinical course, such as their insulin secretion ability, and the dose of insulin injection required were similar. In this family, only the members with MODY3 exhibited primary dyslipidemia, with all members without MODY3 not showing primary dyslipidemia. Interestingly, their father, who had the same mutation in the HNF-1α gene, did not develop MODY3 or primary dyslipidemia, these observations suggest that the development of MODY3 due to an HNF-1α gene mutation may be closely associated with that of primary dyslipidemia.