Seemingly unrelated to the olfactory system, the Kv1.3-/- “Super-smeller” mice have metabolic alterations including an elevated energy expenditure and locomotor activity, irregular ingestive behaviors, resistance to diet- and genetic-induced obesity, and increased insulin sensitivity [8], [10]–[12]. The gene discussed is KCNA3; the disease is obesity due to melanocortin 4 receptor deficiency.