phe·​nyl·​ke·​ton·​uria ˌfe-nᵊl-ˌkē-tᵊn-ˈu̇r-ē-ə How to pronounce phenylketonuria (audio)
: an inherited metabolic disorder caused by an enzyme deficiency resulting in accumulation of phenylalanine and its metabolites in the blood causing usually severe intellectual disability and seizures unless phenylalanine is restricted from the diet beginning at birth
abbreviation PKU
phenylketonuric noun or adjective

Examples of phenylketonuria in a Sentence

Recent Examples on the Web The company’s efforts to convert healthy red blood cells into drugs failed to yield positive results for treatment of the rare genetic disease phenylketonuria (commonly known as PKU); its efforts whiffed again once the company pivoted to cancer treatments. Paolo Confino, Fortune, 10 Aug. 2023 The classic success story is neonatal screening for phenylketonuria [a genetic disorder characterized by the inability to utilize the amino acid phenylalanine], which has saved thousands of children’s brains. Robert Keating, Discover Magazine, 15 Dec. 2010 He was born with phenylketonuria (PKU), the build-up of amino acid called phenylalanine in the body which can cause learning disabilities. Eric Walden, The Salt Lake Tribune, 10 Aug. 2022 The company will move forward with some preclinical programs that were well underway, including drugs for the rare metabolic diseases phenylketonuria, methylmalonic acidemia, and propionic acidemia. Globe Staff,, 12 July 2022 Beichler's two sons, Jax, 7 months, and Taylor, 21 months, were both born with a metabolic condition called classic phenylketonuria (PKU). Georgia Slater,, 30 June 2022 Beichler's two sons Jax, 7 months, and Taylor, 21 months, were both born with classic phenylketonuria (PKU), a metabolic condition that requires them to be on medical-grade formula for life. Georgia Slater,, 1 July 2022 In 1963, Guthrie pioneered a simple test for detecting the genetic disorder phenylketonuria, commonly called PKU, using just a few drops of blood collected from a baby's heel and placed on filter paper. Mark Johnson,, 29 Apr. 2022 Among liver disorders, iECure’s will work on conditions called Ornithine Transcarbamylasedeficiency and phenylketonuria. Aayushi Pratap, Forbes, 9 Sep. 2021 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'phenylketonuria.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


New Latin, from International Scientific Vocabulary phenyl + ketone + New Latin -uria

First Known Use

1935, in the meaning defined above

Time Traveler
The first known use of phenylketonuria was in 1935

Dictionary Entries Near phenylketonuria

Cite this Entry

“Phenylketonuria.” Dictionary, Merriam-Webster, Accessed 8 Dec. 2023.

Kids Definition


phe·​nyl·​ke·​ton·​uria ˌfen-ᵊl-ˌkēt-ᵊn-ˈ(y)u̇r-ē-ə How to pronounce phenylketonuria (audio)
: an inherited disease of human beings that is marked by the inability to break down and process a certain chemical in the body and may cause severe brain damage if not treated properly

Medical Definition


phe·​nyl·​ke·​ton·​uria ˌfen-ᵊl-ˌkēt-ᵊn-ˈ(y)u̇r-ē-ə, ˌfēn- How to pronounce phenylketonuria (audio)
: a metabolic disorder that is caused by an enzyme deficiency resulting in the accumulation of phenylalanine and its metabolites (as phenylpyruvic acid) in the blood and their excess excretion in the urine, that is inherited as an autosomal recessive trait, and that causes usually severe intellectual disability, seizures, eczema, and abnormal body odor unless phenylalanine is restricted from the diet beginning at birth
abbreviation PKU

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