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All Diseases > GTP Cyclohydrolase 1 Deficiency (recessive form)
GTP Cyclohydrolase 1 Deficiency (recessive form) (GTPCH1 deficiency)
Disease Category: Phenylketonuria
A genetic disorder causing high blood levels of the amino acid phenylalanine. This condition also causes abnormally low levels of neurotransmitters, which transmit signals between nerve cells in the brain. When not treated, symptoms include abnormalities of muscle tone, delays in motor development, convulsions, drowsiness, irritability, abnormal movements, hyperthermia, hypersalivation, and difficulty swallowing.