PCSK2 and diabetes mellitus: The aim of the current study is to investigate the association between genetic variants of PCSK2 and fasting insulin and glucose concentration, the homeostasis model assessment of beta cell function (HOMA-beta) and HOMA-IR, various parameters during the 75 g oral glucose tolerance test (OGTT), and clinical progression from normal glucose tolerance to diabetes after a follow-up of 5 years.