UBE2NL and type 2 diabetes mellitus: Gene-level association analysis of rare variants (MAF < 0.5%) identified 4 genes at exome-wide significance: MC4R, PAM, SLC30A8 and UBE2NL. Of note, the association of SLC30A8 with T2D was driven by 90 missense variants, where the reduced protein activity was linked to decreased T2D risk.