Phosphoserine aminotransferase deficiency: a novel disorder of the serine biosynthesis pathway.
Am J Hum Genet
; 80(5): 931-7, 2007 May.
Article
in En
| MEDLINE
| ID: mdl-17436247
ABSTRACT
We present the first two identified cases of phosphoserine aminotransferase deficiency. This disorder of serine biosynthesis has been identified in two siblings who showed low concentrations of serine and glycine in plasma and cerebrospinal fluid. Clinically, the index patient presented with intractable seizures, acquired microcephaly, hypertonia, and psychomotor retardation and died at age 7 mo despite supplementation with serine (500 mg/kg/d) and glycine (200 mg/kg/d) from age 11 wk. The younger sibling received treatment from birth, which led to a normal outcome at age 3 years. Measurement of phosphoserine aminotransferase activity in cultured fibroblasts in the index patient was inconclusive, but mutational analysis revealed compound heterozygosity for two mutations in the PSAT1 gene--one frameshift mutation (c.delG107) and one missense mutation (c.299A-->C [p.Asp100Ala])--in both siblings. Expression studies of the p.Asp100Ala mutant protein revealed a V(max) of only 15% of that of the wild-type protein.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Serine
/
Amino Acid Metabolism, Inborn Errors
/
Transaminases
Type of study:
Prognostic_studies
Limits:
Child, preschool
/
Female
/
Humans
/
Infant
/
Male
/
Newborn
Language:
En
Journal:
Am J Hum Genet
Year:
2007
Document type:
Article
Affiliation country:
United kingdom