The patients studied had homozygous or compound heterozygous variants of POMC, PCSK1 or LEPR deficiency; however, the effect of certain other heterozygous POMC variants in obesity is still elusive, and more in-depth phenotyping of each heterozygote may be helpful.86 Despite the variations reported, setmelanotide is a viable option for patients with genetic obesity, for which it has been approved. The gene discussed is PCSK1; the disease is obesity due to melanocortin 4 receptor deficiency.