What is a common characteristic of Prader-Willi syndrome?

Prader-Willi syndrome is a genetic disorder that is often characterized by obesity, which is a hallmark feature of this condition. Individuals with Prader-Willi syndrome typically experience insatiable hunger and a reduced ability to feel satiated after eating, leading to weight gain and obesity if not carefully managed. The obesity can begin in early childhood and tends to worsen if dietary and lifestyle interventions are not implemented.

While the other options may be associated with various conditions, they do not specifically characterize Prader-Willi syndrome. For instance, excessive energy levels are typically not associated with this syndrome; instead, affected individuals often have low muscle tone and decreased physical activity, which contribute to obesity. High levels of testosterone are not a defining feature, as individuals with Prader-Willi syndrome can experience hormonal imbalances and may even have low testosterone levels, especially in males. Similarly, low birth weight may occur in some infants, but it is not a common or defining characteristic of the syndrome, as many affected individuals are born at a normal weight.

Overall, the predominance of obesity in individuals with Prader-Willi syndrome, resulting from metabolic and behavioral factors, solidifies it as a key characteristic of the condition.