Phenylketonuria, or PKU, is a rare genetic disorder related to metabolism. When people eat proteins, the body breaks these down into amino acids. The body then uses these amino acids to make its own proteins, removing those it doesn't need. Individuals with phenylketonuria lack an enzyme needed to effectively break down phenylalanine, a type of amino acid found in many protein rich foods.
If PKU isn't addressed, a buildup of phenylalanine may have serious effects. Phenylketonuria can't be cured, but it may be managed by dietary controls. If phenylketonuria symptoms are suspected in a child, urgent medical advice should be sought.1‘Phenylketonuria.’ NHS.uk, 19 Oct. 2017, www.nhs.uk/conditions/phenylketonuria/
The body uses the amino acid phenylalanine to create melanin, a natural pigment that determines a person's skin color. The body's inability to break down phenylalanine may lead to lower levels of melanin.
People with low amounts of melanin generally have pale skin. If a child has much fairer skin than their immediate family members, it may indicate the presence of phenylketonuria. Individuals with phenylketonuria may also have other skin problems, including rashes, hardened lesions and light sensitivity. People with lighter skin tones are at greater risk of sunburn too.2Murphy, Brian. ‘Phenylketonuria and Your Skin.’ Phenylketonuria News, 17 Sept. 2020, phenylketonurianews.com/2020/09/17/phenylketonuria-and-your-skin/