In a rigorously phenotype cohort of 286 children (mean age 7.2 ± 2.7 years), OSA-affected individuals—particularly those with comorbid obesity (OSA + OB)—exhibited significantly elevated circulating concentrations of Aβ42 and presenilin-1 (PS1) (p < 0.001 versus age-matched controls). The gene discussed is PSEN1; the disease is obesity due to melanocortin 4 receptor deficiency.