The compound heterozygous carriers of pathogenic genetic variants in the autosomal recessive genes LEP, LEPR, POMC and PCSK1 are rare, obesity-associated variants in the autosomal dominant gene MC4R are the most common, with 0.8% of participants in our study carrying a variant in MC4R (13, 35, 36). The gene discussed is PCSK1; the disease is obesity due to melanocortin 4 receptor deficiency.