What is the most common inherited, non-polygenic syndrome that may promote obesity?

The most common inherited, non-polygenic syndrome that may promote obesity is Prader-Willi syndrome. This condition is characterized by a range of physical, mental, and behavioral problems, one of the most notable being a profound hyperphagia (increased appetite). Individuals with Prader-Willi syndrome often suffer from obesity due to the lack of regulation of appetite and food intake, largely stemming from absent or deficient genes located on chromosome 15.

Prader-Willi syndrome's obesity begins in childhood, as affected individuals have a constant urge to eat, leading to excessive weight gain if not managed properly. The inability to adequately control hunger and satiety is a hallmark of the syndrome, making it a significant factor in understanding the genetic implications of obesity.

The other conditions listed, such as melanocortin 4 receptor deficiency, leptin receptor deficiency, and Angelman syndrome, while associated with metabolic or neurobehavioral issues, do not have the same prevalence or typical behavioral patterns related to obesity as does Prader-Willi syndrome. Therefore, Prader-Willi syndrome stands out as the most recognized hereditary condition that directly influences body weight and obesity outcomes.