TCF7L2 and metabolic disease: Further, the variants linked to ADAMTS9, HSD17B12, TCF7L2, KAT8, NT5C2, and GLN3 seem to be mostly associated with metabolic phenotypes as opposed to non-metabolic disease traits (Fig 3C, brown labels indicate genes with the largest proportion of metabolic traits), suggesting these genes may have a rather specific role in metabolic health.