5 Disorders of Histidine Metabolism
Nenad Blau
5.1 Introduction
Histidinemia, urocanase deficiency, and formiminotransferase deficiency are harmless disorders, although treatment might be considered in a histidine- mic infant who is symptomatic (< 1%; Levy et al. 2001). A few patients with speech impairment were found to be mentally retarded. It appears that clinical abnormalities in these patients are coincidental.
5.2 Nomenclature
No. Disorder Definitions/comment Gene Symbol OMIM No.
5.1 Histidinemia Histidine ammonia-lyase
deficiency
HAL 235800
5.2 Urocanase deficiency 276880
5.3 Formiminotransferase deficiency FTCD 229100
5.3 Treatment and Follow-up Generally no treatment required.
I Symptomatic Patients
5.1 Histidinemia Low-His diet
5.3 Formiminotransferase deficiency Folinic acid, 15 mg/day
References
1. Levy HL, Taylor RG, McInnes RR (2001) Disorders of histidine metabolism. In: Scriver CR, Beaudet AL, Sly WS, Valle D, Childs B, Vogelstein B (eds) The metabolic and molecular bases of inherited disease, 8th edn.: McGraw-Hill, New York pp 1807–1820
