Unravelling 5-oxoprolinuria (pyroglutamic aciduria) due to bi-allelic OPLAH mutations: 20 new mutations in 14 families.
Mol Genet Metab
; 119(1-2): 44-9, 2016 09.
Article
in En
| MEDLINE
| ID: mdl-27477828
ABSTRACT
Primary 5-oxoprolinuria (pyroglutamic aciduria) is caused by a genetic defect in the γ-glutamyl cycle, affecting either glutathione synthetase or 5-oxoprolinase. While several dozens of patients with glutathione synthetase deficiency have been reported, with hemolytic anemia representing the clinical key feature, 5-oxoprolinase deficiency due to OPLAH mutations is less frequent and so far has not attracted much attention. This has prompted us to investigate the clinical phenotype as well as the underlying genotype in patients from 14 families of various ethnic backgrounds who underwent diagnostic mutation analysis following the detection of 5-oxoprolinuria. In all patients with 5-oxoprolinuria studied, bi-allelic mutations in OPLAH were indicated. An autosomal recessive mode of inheritance for 5-oxoprolinase deficiency is further supported by the identification of a single mutation in all 9/14 parent sample sets investigated (except for the father of one patient whose result suggests homozygosity), and the absence of 5-oxoprolinuria in all tested heterozygotes. It is remarkable, that all 20 mutations identified were novel and private to the respective families. Clinical features were highly variable and in several sib pairs, did not segregate with 5-oxoprolinuria. Although a pathogenic role of 5-oxoprolinase deficiency remains possible, this is not supported by our findings. Additional patient ascertainment and long-term follow-up is needed to establish the benign nature of this inborn error of metabolism. It is important that all symptomatic patients with persistently elevated levels of 5-oxoproline and no obvious explanation are investigated for the genetic etiology.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Pyroglutamate Hydrolase
/
Pyrrolidonecarboxylic Acid
/
Amino Acid Metabolism, Inborn Errors
/
Glutathione Synthase
Type of study:
Prognostic_studies
Limits:
Adolescent
/
Child
/
Child, preschool
/
Female
/
Humans
/
Infant
/
Male
Language:
En
Journal:
Mol Genet Metab
Journal subject:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
/
METABOLISMO
Year:
2016
Document type:
Article