Cases with distal 16p11.2 BP2-BP3 deletions on average had an earlier onset of obesity (5.1 years versus 9.8 years; p = 0.044), as well as a higher BMI SDS ( + 3.2 versus +1.5; p < 0.001). Here, IGFBP2 is linked to obesity due to melanocortin 4 receptor deficiency.