Phenylketonuria

Marinella Buckley

What is it and what are its effects on the body?

Phenylketonuria is what happens when you have too much phenylalanine in your blood. This genetic disease can have many bad effects if not treated properly or treated at all. Possible effects on the body/mind are delayed development, psychiatric disorders, and behavior problems. Other effects are seizures, uncontrollable movements, tremors, and hyperactivity. People with this problem can also have a head size below normal, a musty odor, or lighter skin and hair than family.

How do you get it and what is the cause?

The way you get this genetic disease is if the gene is passed down from both parents. It isn't sex-linked or on a specific chromosome. People who have phenylketonuria have an autosomal recessive pattern condition - the trait is recessive.


This disorder happens because of a mutation in the PAH gene that causes the enzyme called phenylalanine hydroxylase to be missing. This enzyme is supposed to convert a substance called phenylalanine into other compounds for the body. Too much phenylalanine build-up in the blood can be very dangerous to your health and cause many complications, like those listed above.

How is it diagnosed and treated for?

Phenylketonuria can be diagnosed easily with a blood test. You can't completely get rid of it, but there are things you can do to reduce the symptoms. The main thing that you do to treat this disease yourself is live on a low phenylalanine diet. It consists of only eating foods with very little phenylalanine in them. Mental development can also be improved with supplements like fish oil supplements.

How common is it?

There is no certain "type" of person that is more likely to get phenylketonuria than someone else. Any person can get it if they get the gene passed down to them. Most of the time only 1 person out of about every 13,000 ends of inheriting phenylketonuria. There's about a 1 in 4 chance of offspring of parents with the condition being affected.
Another name for this genetic disorder is Folling's disease or PKU, which are both way easier to pronounce than Phenylketonuria.