|
Diagnosis
of Glycine Encephalopathy (NKH)
·
Amino Acid analysis
Performed on plasma and CSF.
Collect plasma and CSF samples at the same time for determination of the ratio
of plasma glycine to CSF glycine.
·
Enzyme assay
Performed on liver,
lymphoblasts, uncultured CVS.
·
Molecular diagnosis
Between 10-35% of patients have a defect in the T protein (aminomethyl
transferase) gene and the rest of the patients have a defect in the P protein
(glycine decarboxylase) gene.
Defects in the H protein gene are very rare. Defects in the L protein cause a
different type of disease.
Most patients will be compound heterozygotes.
Mutation search is costly and may be family specific.
Resources for enzyme and molecular testing:
·
Dr Brett Casey
Molecular Genetics Laboratory
Children's Hospital
Vancouver, British Columbia, Canada
E-mail: bcasey@cw.bc.ca
Services: Dr. Casey is willing to work with clinical geneticists to
begin mutation searches for families.
·
Dr. Rhona Jack
Children's Hospital
Seattle, Washington
Phone: 206-987-2569
E-mail: rhona.jack@seattlechildrens.org.
Services: Liver enzyme assays should be available in early 2004
·
Dr George Gray
Clinical Chemistry
Children's Hospital
Birmingham, UK
E-mail: george.gray@bch.nhs.uk
Web Page: www.bch.org.uk/departments/imd/laboratoryservice.htm
Services: Prenatal diagnosis by enzyme assay in uncultured CVS. Screening of DNA for five common
mutations.
·
Marie O. Rolland
Hopital Debrousse
Service de Biochimie Pediatrique
Lyon, France
Phone: 33-0470238-5715
E-mail: mo.rolland@chu-lyon.fr
Services: Prenatal testing
|
