Hypertriglyceridemia as a main feature associated with 17q12 deletion syndrome-related hepatocyte nuclear factor 1β-maturity-onset diabetes of the young.

Maturity-onset diabetes of the young type 5 (MODY5) may be caused by heterozygous point mutations or whole gene deletion of HNF1B. Recent studies revealed that complete deletion of the HNF1B gene may be part of the 17q12 deletion syndrome with multi-system involvement. The length of the deletion can contribute to the phenotypic variability in patients with HNF1B-MODY due to whole gene deletion. Using next-generation sequencing alone to diagnose MODY could miss a whole gene deletion or copy number variations. Specialized detection methods such as microarray analysis or low-pass whole genome sequencing are required to accurately diagnose HNF1B-MODY as a component of the 17q12 deletion syndrome. Molecular diagnosis is necessary to distinguish other acquired cystic kidney diseases in patients with type 2 diabetes which could phenocopy HNF1B-MODY. Hypertriglyceridemia is a possible metabolic feature in patients with HNF1B-MODY due to 17q12 deletion syndrome.