Is MC4R useful for Langlebigkeit?

MC4R (melanocortin 4 receptor) is a gene involved in appetite regulation and energy balance. Certain variants are associated with early-onset obesity. For longevity, MC4R is not a well-established biomarker. The link is indirect: obesity can shorten lifespan, but MC4R variants account for only a small fraction of weight variation. Evidence for a direct effect on longevity is weak and mostly based on association studies. Genetic testing for MC4R may be useful in cases of unexplained severe obesity, but it is not a primary tool for longevity optimization. Lifestyle factors (diet, exercise, stress) are far more impactful. Caveat: common MC4R variants have low clinical penetrance; rare loss-of-function mutations are more significant but uncommon.