Phenylketonuria

Phenylketonuria, also known as PKU is a disease that affects the way your body breaks down proteins. PKU is an autosomal recessive inherited disease, so you inherit one infected chromosome from your mom and one infected chromosome from your dad. If you were looking at the karyotype of someone with this disease, you would notice that there is a mutation in a gene on chromosome 12. This mutation is a protein gene mutation that codes for protein PAH. If someone does not have enough PAH, phenylalanine builds up in their blood, which leads to poisoning their nerve cells. When babies are first born, they show no signs. If they continue living without being treated, they can get severe brain damage, such as Epilepsy. This can also give them behavioral problems and stunt their growth. Other signs can be eczema, musty body odor, small head and fair skin. When babies are first born they are tested for this disease. A small blood sample is take from their heel or arm and the doctors test it for the level of phenylalanine. If there is a high level of phenylalanine, then the baby has the disease. If you have the disease you need to eat a protein-free diet because many proteins contain phenylalanine. Infants are given a special formula that does not contain phenylalanine. As you get older with this disease, you need to avoid protein rich foods, such as meats, cheeses, nuts and eggs. On average one out of every fifteen thousand babies are born with this disease. If you follow the specific diets of this disease the life expectancy is the same as if you lived regularly.