The six patients harbouring pathogenic RSVs in MC4R were males with a BMI above + 5.5 standard deviation score (SDS), orexigenic impulsivity, hyperinsulinism, some overgrowth (height >+1 SDS over target height) and advanced bone age (14 months on average), a phenotype previously defined in patients with MC4R mutations [43, 44]. This evidence concerns the gene MC4R and hyperinsulinism.