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Published on: June 9, 2018
Phenotypic and genotypic variability in Alpers syndrome.
Kalliopi Sofou1, Ali-Reza Moslemi, Gittan Kollberg
1Department of Pediatrics, University of Gothenburg, The Queen Silvia's Children Hospital, S-416 85 Gothenburg, Sweden. kalliopi.sofou@vgregion.se
Summary
Alpers syndrome presents differently based on POLG1 mutations. This study differentiates phenotypes in children with mitochondrial disorders, highlighting distinct neurological and organ involvement.
Area of Science:
- Pediatric Neurology
- Mitochondrial Medicine
- Genetics
Background:
- Alpers syndrome is a common childhood mitochondrial disorder.
- Pathogenic mutations in POLG1 are frequently associated with Alpers syndrome.
Purpose of the Study:
- Investigate genotype-phenotype correlations in Alpers syndrome.
- Differentiate Alpers syndrome patients with and without POLG1 mutations.
Main Methods:
- Retrospective analysis of 19 pediatric patients diagnosed with Alpers syndrome (1984-2007).
- Included biochemical, morphological, and genetic investigations.
- POLG1 mutation analysis and complete mtDNA sequencing.
Main Results:
- Six patients had POLG1 mutations; one novel mutation identified.
- POLG1(+) patients showed more seizures and stroke-like episodes.
- POLG1(-) patients more frequently presented with microcephaly and spasticity.
- Hepatic (79%) and ophthalmological (88%) involvement were common.
- Predominant complex I deficiency observed in most patients.
Conclusions:
- Alpers syndrome is a heterogeneous condition presenting with early-onset progressive cortical encephalopathy.
- Clinical phenotypes differ significantly based on the presence or absence of POLG1 mutations.
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