Plausible Explanation (Requiring Further Validation): The mechanisms linking PA to obesity (energy balance [43], insulin sensitivity [44], self-regulation) are well-established in physiology/behavioral science, though we did not measure them directly here, also, unaccounted confounders such as dietary patterns and sleep duration may influence the observed relationships. The gene discussed is INS; the disease is obesity due to melanocortin 4 receptor deficiency.