SLC39A5 and type 2 diabetes mellitus: Given the apparent complexity of the system, we chose to take a human genetics approach to search for zinc transporter genes associated with metabolic traits and discovered a novel association of LOF variants in SLC39A5 with increased circulating zinc (p=4.9 × 10–4) and a reduced risk of T2D (OR 0.82, 95% CI 0.68–0.99, p=3.7 × 10–2).