Melanocortin 4 receptor mutations become common.

In a new paper, Wade et al. (2021) analyzed the frequency of MC4R loss-of-function (LoF) mutations in a population-based Avon Longitudinal Study of Parents and Children. The frequency was 1 in 337 and the authors showed that MC4R LoF variants significantly correlated with increased body weight and fat mass in children and adults (cumulating in additional 17.76 kg weight in adulthood). Hence, the authors provide evidence that MC4R LoF variants are more common than previously expected.