Angelman and Prader-Willi syndromes are intriguing related conditions. Each arises from missing the same small section of chromosome 15, but one develops if the gap comes from the female parent, the other if it comes from the male.
A Peculiar Pair of Disorders
Prader-Willi syndrome is the more distinctive, and therefore more likely to make headlines.
A newborn with Prader-Willi is small and struggles to put on weight. A toddler becomes obsessed with eating as metabolism slows precipitously. Frantic parents lock kitchen cabinets, garbage cans, and refrigerators to keep their children from eating until their digestive organs burst.
The brain's hypothalamus malfunctions and can't regulate appetite, and so children can't sense when they are full. Plus, their stomachs do not empty quickly enough. The unremitting hunger becomes life-threatening.
In contrast, a child with Angelman syndrome has autism spectrum disorder and intellectual disability, an extended tongue, large jaw, poor coordination, and convulsions that make the arms flap. The distinctive facial features led Harry Angelman, when he described the condition in 1962, to call affected individuals "puppet children." In 1982 "Angelman syndrome" replaced the derogatory puppet comparison.
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