Phenylketonuria (commonly known as PKU) is a rare but potentially serious inherited disorder.
Our bodies break down the protein in foods, such as meat and fish, into amino acids, which are the “building blocks” of protein.
These amino acids are then used to make our own proteins. Any amino acids that are not needed are broken down further and removed from the body.
People with PKU cannot break down the amino acid phenylalanine, which then builds up in their blood and brain. This can lead to brain damage.
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