PKU is a chromosomal disease caused by a mutation on chromosome 12. There is a special band called 12q23-2, where the specific PAH gene is located. There are several hundred diseases caused by mutations on the PAH gene. This mutation causes the body to not be able to process the amino acid phenylalanine, causing it to be built up in the blood. Several symptoms of PKU include:
  • patients may expenience seizures due to high concentrations of Phenyalanine being toxic to the brain.
  • mental retardation can occur if too much if exposed to the brain.
  • psychiatric disorders
  • musty or mouse-like smell from excess phenyalanine
  • lighter hair and skin than unaffected family members
  • hyperactivity
  • stunted growth
  • skin rashes
  • small head size

aa_chart.pngThe red amino acid is phenyalanine, which the body can't process with PKU.
Treatments: The treatments are a strict diet and pku formula
  • the diet includes a very low amount of phenylalanine which can be found in milk, eggs, cheese, nuts, soybeans, beans, chicken, steak and other beef products, pork, fish, chocolate candy, peas, and beer, they should also avoid diet sodas, and meds with aspartame
  • they can have limited portions of fruit, vegetables, and desserts.
  • some therapeutic options are as followed
  • enzyme therapy: process were with enzyme deficiency with pku by giving patients with the capabilities to matabolizing Phe. The researchers are testing the use of various enzymes for this purpose.
  • genetherapy: process similar to enzyme therapy but this allows vivo production of the PAH enzyme.
  • LNNA therapy: supplemental levels of ither chemicals occuring in LNAA.

How is PKU Inherited: PKU is inherited by two PAH genes from both parents and it is passed down and a 25% chance to have a child with PKU. This disease is not contagious but out of 12 genes of both parents one of them is mutated.
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external image phenyl.gif

Interesting facts: 1. A norwegian doctor named Asbjørn Følling discovered PKU in 1934.
2. About 1 in every 15000 babies have PKU in the United States.
3. PKU contains PAH which is an enzyme in the liver.

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