Mayo Clinic Health Manager
Get free personalized health guidance for you and your family.
Get StartedRisk factors
By Mayo Clinic staffBoth parents must pass along a copy of the mutated PKU gene for their child to develop the condition. If only one parent has the PKU gene, there's no risk of passing PKU to a child. The gene defect occurs mainly in people of Northern European and Native American ancestry. It's much less common in blacks, Asians and Hispanics.
Children of mothers who have PKU but who didn't follow the PKU diet during pregnancy also may be affected. Although these children don't often have PKU, they do have consequences of the high level of phenylalanine in the mother's blood.
- Bodamer OA. Overview of phenylketonuria. http://www.uptodate.com/home/index.html. Accessed Aug. 18, 2009.
- Phenylketonuria. Genetics Home Reference. http://ghr.nlm.nih.gov/condition=phenylketonuria. Accessed Aug. 27, 2009.
- PKU (Phenylketonuria). March of Dimes. http://www.marchofdimes.com/professionals/14332_1219.asp. Accessed Aug. 24, 2009.
- Longo Nicola. Inherited disorders of amino acid metabolism in adults. In: Fauci AS, et al. Harrison's Principles of Internal Medicine. 17th ed. New York, N.Y.: McGraw Hill Medical; 2008. http://www.accessmedicine.com/content.aspx?aID=2882866. Accessed Aug. 27, 2009.
- Amino acid and organic acid metabolism disorders. The Merck Manuals: The Merck Manual for Healthcare Professionals. http://www.merck.com/mmpe/print/sec19/ch296/ch296c.html. Accessed Aug. 27, 2009.