Other Names for this Disease
- Phenylalanine hydroxylase deficiency
- Oligophrenia phenylpyruvica
- Folling disease
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Phenylalanine is a building block of proteins (an amino acid) that is obtained through the diet. If PKU is not treated, phenylalanine can build up to harmful levels in the body. The signs and symptoms of PKU vary from mild to severe. The most severe form of this disorder is known as classic PKU. Without treatment, these children develop permanent intellectual disability. Light skin and hair, seizures, delayed development, behavioral problems, and psychiatric disorders are also common. Less severe forms of this condition, sometimes called variant PKU and non-PKU hyperphenylalaninemia, have a smaller risk of brain damage. Babies born to mothers with PKU and women who no longer follow a low-phenylalanine diet have a risk of intellectual disability because they are exposed to very high levels of phenylalanine before birth. PKU is caused by changes (mutations ) in the PAH gene. It is inherited in an autosomal recessive manner. Because PKU can be detected by a simple blood test and is treatable, newborn screening is available for this disorder. The best treatment for PKU is a diet of low-protein foods.Phenylketonuria (PKU) is an inherited disorder that increases the levels of phenylalanine in the blood.
Last updated: 12/28/2015
- Phenylketonuria. Genetics Home Reference Web site. February, 2012; http://ghr.nlm.nih.gov/condition=phenylketonuria. Accessed 12/28/2015.
- Mitchell JJ. Phenylalanine Hydroxylase Deficiency. GeneReviews. January 31, 2013; http://www.ncbi.nlm.nih.gov/books/NBK1504/. Accessed 12/28/2015.
- Phenylketonuria. MedlinePlus Web site. December 23 2015; http://www.nlm.nih.gov/medlineplus/phenylketonuria.html. Accessed 12/28/2015.
- The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) provides information related to the health of children, adults, and families. Click on the link to view information on this topic.
- Genetics Home Reference (GHR) contains information on Phenylketonuria. This website is maintained by the National Library of Medicine.
- MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
- MedlinePlus a service of the National Library of Medicine (NLM) at the National Institutes of Health (NIH) provides an encyclopedia article about phenylketonuria (PKU). To view the article, click on the MedlinePlus link.
- The National Human Genome Research Institute's (NHGRI) mission encompasses a broad range of studies aimed at understanding the structure and function of the human genome and its role in health and disease. Click on the link to view the information page on this topic.
- The National Organization for Rare Disorders (NORD) is a federation of more than 130 nonprofit voluntary health organizations serving people with rare disorders. Click on the link to view information on this topic.
- The Screening, Technology And Research in Genetics (STAR-G) Project has a fact sheet on this condition, which was written specifically for families that have received a diagnosis as a result of newborn screening. This fact sheet provides general information about the condition and answers questions that are of particular concern to parents.
- Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
- Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Phenylketonuria. Click on the link to view a sample search on this topic.