Phenylketonuria (PKU) is a rare, inherited disease that strikes about one in 12,000 babies in North America (approximately 300 babies per year).
If it isn’t treated promptly in the first few weeks after birth, it can lead to developmental delays and neurological problems. PKU cannot be cured, but certain treatments can help keep the disease under control. In Canada, PKU is one of the diseases that babies are systemically screened for at birth. Infants who test positive can therefore receive immediate treatment in order to prevent complications caused by the disease.
People with PKU have a defective gene that prevents them from producing an enzyme called phenylalanine hydroxylase (PHA). Our bodies absolutely need PHA to transform phenylalanine into tyrosine. Phenylalanine is one of the components in protein, so if PHA is absent, phenylalanine accumulates in the brain and other tissues, causing major neurological damage.
The treatment for PKU involves eliminating phenylalanine from the diet. Since phenylalanine is found in all natural proteins, people with PKU cannot eat any protein found in nature. They must therefore consume a synthetic protein formula designed specifically for persons with PKU. In addition to this protein formula, PKU patients must follow a very strict diet. If they follow this diet very closely, individuals with PKU can develop normally and have a normal life expectancy.