One mutation in the galactocerebrosidase gene is responsible for a majority of mutant alleles in Northern European patients with infantile Krabbe disease
- Jefferson Medical College, Philadelphia, PA (United States); and others
Globoid cell leukodystrophy (GCL) or Krabbe disease is an autosomal recessive disorder resulting from a deficiency of galactocerebrosidase (GALC) activity. The typical human patient presents with symptoms of spasticity, developmental delay and irritability by 6 months of age. Older patients, including adults, are also diagnosed with this disorder. While patients from all ethnic groups are included within the more than 230 patients diagnosed in this laboratory, many trace their ancestry to Northern Europe. Patients are easy to diagnose by their low GALC activity. However, carriers are difficult to identify due to a large overlap in the {open_quotes}control{close_quotes} and carrier ranges. With our cloning of the GALC gene we have undertaken a study to identify mutations causing GCL in some of our families. We have identified a C to T transition at position {open_quotes}502{close_quotes} (counting form the A of the initiation codon) in about 65% of the mutant alleles in patients with Northern European ancestry. Identification of an intron 32 nucleotides downstream from the site of the mutation permits amplification of genomic DNA samples and rapid cycle sequencing. This mutation was found primarily in classic infantile patients, however it was found in the heterozygous state in a juvenile patient and in an African-American patient. This mutation changes the codon for arginine to one for cysteine, and computer analysis predicts a significant change in the secondary structure of this multi-subunit enzyme. A G to A transition at position {open_quotes}694{close_quotes} was found in the homozygous state in another infantile patient from a consanguineous mating. We are in the process of looking for this mutation in other patients. It is hoped that a few mutations will be found to be responsible for infantile Krabbe disease so that carrier identification can be improved for some families.
- OSTI ID:
- 133426
- Report Number(s):
- CONF-941009-; ISSN 0002-9297; TRN: 95:005313-0154
- Journal Information:
- American Journal of Human Genetics, Vol. 55, Issue Suppl.3; Conference: 44. annual meeting of the American Society of Human Genetics, Montreal (Canada), 18-22 Oct 1994; Other Information: PBD: Sep 1994
- Country of Publication:
- United States
- Language:
- English
Similar Records
Structure and organization of the human galactocerebrosidase (GALC) gene
Localization of the Krabbe disease gene (GALC) on chromosome 14 by multipoint linkage analysis