MTNR1B and type 2 diabetes mellitus: Despite these constraints, confirmed rare variant associations include: (i) plasma lipid concentrations with ABCA1, APOA1, LCAT, NPC1L1 and ANGPTL4 [36–38]; (ii) body mass index with monogenic obesity-related genes [39]; (iii) blood pressure with renal salt handling genes [40]; (iv) hypertriglyceridemia with lipoprotein lipase [41]; (v) inflammatory bowel disease with NOD2 [42]; and (vi) type 2 diabetes with MTNR1B [43].