n. Abbr. PKU A genetic disorder in which the body lacks the enzyme necessary to metabolize phenylalanine to tyrosine. Left untreated, the disorder can cause brain damage and progressive intellectual disability as a result of the accumulation of phenylalanine and its breakdown products. [phenylketone, the class of organic compounds including phenylpyruvic acid, a breakdown product of phenylalanine that is abnormally abundant in the urine of those having the disorder (PHENYL + KETONE) + UR(O)-1 + -IA1.] phen′yl·ke′to·nuric adj. & n. |
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