Joseph+Mahony

PKU - Phenylketonuria

__Description of PKU:__ PKU is a rare condition in which a baby is born without the ability to break down an amino acid called phenylalanine or PHE. When someone who has PKU eats protein, each amino acid in the protein is broken down, one of these amino acids is the PHE amino acid, the person carrying this disease lacks the PAH enzyme used to break down PHE. As a result PHE will continue to build to toxic levels which will lead to many problems. __Initial symptoms of disease: __ There are no initial symptoms of newborns with PKU, babies have to have their blood tested in order to test for PKU. However while there are no initial symptoms, babies left untreated will show signs of PKU within a few months. As a result of no initial symptoms, all states in the U.S. require PKU testing at birth. __Common treatments: __ The primary treatment for PKU is a strict diet of as low as possible PHE intake by staying away from foods high in protein. Through a long period of testing, the person with PKU will find the absolute necessary amount of proteins to have in order to still remain healthy but keep the levels of PHE at a safe level. A new emerging form of helping to treat PKU is a neutral amino acid therapy tablet which blocks some absorption of PHE. __Side effects of the disease and the treatments:__ From this disease comes many problems: Mental retardation, behavioral/social problems, seizures, hyperactivity, stunted growth, skin rashes (eczema), small head size (microcephaly), a musty odor caused by the build up of PHE, light skin and light hair because PHE cannot transform into melanin, the pigment responsible for skin and hair color.

__ Prevention or control of the disease: __ For women with PKU, follow a low PHE diet before becoming pregnant. Also, genetic counseling to asses your risks of passing down the disease to assist with family planning.

__Chromosomes associated with disease:__ The PKU disease is associated with chromosome 12, the gene on the chromosome being mutated is the PAH gene.

__How is PKU inherited?__ PKU is a autosomal recessive trait, meaning it takes both genes to be mutated to make a person have PKU. If a person only has one mutated gene then they are only carriers of the disease. So this means both parents must be at least carriers of the disease to pass it on to their child.

__Populations with predispositions to disease:__ The gene defect mainly occurs in Americans and Europeans, the disease is much less common in Asians and Latinos and is least common in Africa.

__Works Cited:__ Board, A.D.A.M. Editorial. "Phenylketonuria." //Phenylketonuria //. U.S. National Library of Medicine, 18 Nov. 2011. Web. 10 Feb. 2013. .

Schuett, Virginia, and Selma Snyderman. "Phenylketonuria: How Is It Inherited?" //Phenylketonuria: How Is It Inherited? // DNA Learning Center, n.d. Web. 10 Feb. 2013. .

Staff, Mayo Clinic. "Definition." //Mayo Clinic //. Mayo Foundation for Medical Education and Research, 17 Nov. 2011. Web. 10 Feb. 2013. .