Array CGH improves detection of mutations in the GALC gene associated with Krabbe disease.
Orphanet J Rare Dis
; 7: 38, 2012 Jun 15.
Article
in En
| MEDLINE
| ID: mdl-22704718
ABSTRACT
BACKGROUND:
Krabbe disease is an autosomal recessive lysosomal storage disorder caused by mutations in the GALC gene. The most common mutation in the Caucasian population is a 30-kb deletion of exons 11 through 17. There are few other reports of intragenic GALC deletions or duplications, due in part to difficulties detecting them. METHODS ANDRESULTS:
We used gene-targeted array comparative genomic hybridization (CGH) to analyze the GALC gene in individuals with Krabbe disease in whom sequence analysis with 30-kb deletion analysis identified only one mutation. In our sample of 33 cases, traditional approaches failed to identify two pathogenic mutations in five (15.2%) individuals with confirmed Krabbe disease. The addition of array CGH deletion/duplication analysis to the genetic testing strategy led to the identification of a second pathogenic mutation in three (9.1%) of these five individuals. In all three cases, the deletion or duplication identified through array CGH was a novel GALC mutation, including the only reported duplication in the GALC gene, which would have been missed by traditional testing methodologies. We report these three cases in detail. The second mutation remains unknown in the remaining two individuals (6.1%), despite our full battery of testing.CONCLUSIONS:
Analysis of the GALC gene using array CGH deletion/duplication testing increased the two-mutation detection rate from 84.8% to 93.9% in affected individuals. Better mutation detection rates are important for improving molecular diagnosis of Krabbe disease, as well as for providing prenatal and carrier testing in family members.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Comparative Genomic Hybridization
/
Galactosylceramidase
/
Leukodystrophy, Globoid Cell
Type of study:
Diagnostic_studies
/
Risk_factors_studies
Limits:
Female
/
Humans
/
Infant
/
Male
Language:
En
Journal:
Orphanet J Rare Dis
Journal subject:
MEDICINA
Year:
2012
Document type:
Article
Affiliation country:
United States