HYPERPHENYLALANIEMIA DUE TO GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE DEFICIENCY

Q: What is HYPERPHENYLALANIEMIA DUE TO GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE DEFICIENCY?

rare (<1:1000000) autosomal recessive mutations in the guanosine triphosphate cyclohydrolase 1 (GCH1) gene BH4- or combined BH4-phenylalanine loading test abnormal

Q: Gibt es eine deutsche Bezeichnung?

Hyperphenylalaninämie; GTP-Cyclohydrolase I-Mangel; Hyperphenylalaninämie mit Tetrahydrobiopterin-Mangel, B; GTPCH-Man

Question 1

What is  HYPERPHENYLALANIEMIA DUE TO GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE DEFICIENCY?

Accepted Answer

rare (<1:1000000)
autosomal recessive
mutations in the guanosine triphosphate cyclohydrolase 1 (GCH1) gene
BH4- or combined BH4-phenylalanine loading test abnormal

Question 2

Gibt es eine deutsche Bezeichnung?

Accepted Answer

Hyperphenylalaninämie; GTP-Cyclohydrolase I-Mangel; Hyperphenylalaninämie mit Tetrahydrobiopterin-Mangel, B; GTPCH-Man

Question 3

What is the link to OMIM ?

Accepted Answer

OMIN 233910

Question 4

Which enzymes are involved?

Accepted Answer

GTP cyclohydrolase 1

Disease	HYPERPHENYLALANIEMIA DUE TO GUANOSINE TRIPHOSPHATE CYCLOHYDROLASE DEFICIENCY
Synonym	GTP CYCLOHYDROLASE I DEFICIENCY; GTPCH DEFICIENCY
OMIM	233910 OMIM = Online Mendelian Inheritance of Men
Orphanet	2102
Protein (UniProt)	GTP cyclohydrolase 1
ExPASy	3.5.4.16
Gene locus	14q22.2
ICD	E70.1
Summary	rare (<1:1000000) autosomal recessive mutations in the guanosine triphosphate cyclohydrolase 1 (GCH1) gene BH4- or combined BH4-phenylalanine loading test abnormal
Laboratory findings	Homovanillic acid (HVA) dec (cerebrospinal fluid) 5-Hydroxyindolacetic acid (5-HIAA) dec (cerebrospinal fluid) Biopterin dec (urine) Biopterin dec (cerebrospinal fluid) Guanosine triphosphate cyclohydrolase dec (liver) Neopterin dec (cerebrospinal fluid) Neopterin dec (urine) Phenylalanine inc (plasma) Phenylalanine inc (cerebrospinal fluid) Phenylalanine normal/inc (urine)
Symptoms	feeding difficulties, poor feeding hypotonia drooling EEG abnormalities [-] hypersalivation hyperthermia hypertonia, spasticity irritability lethargy, drowsiness, apathy mental retardation microcephaly (<2 SD for age) neurological deterioration onset, infancy onset, neonatal progressive neurologic defect seizures swallowing difficulties temperature instability