Article

Application of oligonucleotide array CGH in the detection of a large intragenic deletion in POLG associated with Alpers Syndrome.

Murdoch Childrens Research Institute and Genetic Health Services Victoria, Royal Children's Hospital, Melbourne, Australia.
Mitochondrion (Impact Factor: 3.52). 01/2011; 11(1):104-7. DOI: 10.1016/j.mito.2010.07.012
Source: PubMed

ABSTRACT Mutations in the polymerase γ (POLG) gene are among the most common causes of mitochondrial disease and more than 160 POLG mutations have been reported. However, a large proportion of patients suspected of having POLG mutations only have one (heterozygous) definitive pathogenic mutation identified. Using oligonucleotide array CGH, we identified a compound heterozygous large intragenic deletion encompassing exons 15-21 of this gene in a child with Alpers syndrome due to mtDNA depletion. This is the first large POLG deletion reported and the findings show the clinical utility of using array CGH in cases where a single heterozygous mutation has been identified in POLG.

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