NDUFA2 complex I mutation leads to Leigh disease.
Mitochondrial isolated complex I deficiency is the most frequently encountered OXPHOS defect. We report a patient with an isolated complex I deficiency expressed in skin fibroblasts as well as muscle tissue. Because the parents were consanguineous, we performed homozygosity mapping to identify homozygous regions containing candidate genes such as NDUFA2 on chromosome 5. Screening of this gene on genomic DNA revealed a mutation that interferes with correct splicing and results in the skipping of exon 2. Exon skipping was confirmed on the mRNA level. The mutation in this accessory subunit causes reduced activity and disturbed assembly of complex I. Furthermore, the mutation is associated with a mitochondrial depolarization. The expression and activity of complex I and the depolarization was (partially) rescued with a baculovirus system expressing the NDUFA2 gene.
Department of Pediatrics, Nijmegen Center for Mitochondrial Disorders, Radboud University Nijmegen Medical Center, Nijmegen 6500 HB, The Netherlands.
Saskia J G
SJ
Hoefs
Cindy E J
CE
Dieteren
Felix
F
Distelmaier
Rolf J R J
RJ
Janssen
Andrea
A
Epplen
Herman G P
HG
Swarts
Marleen
M
Forkink
Richard J
RJ
Rodenburg
Leo G
LG
Nijtmans
Peter H
PH
Willems
Jan A M
JA
Smeitink
Lambert P
LP
van den Heuvel
D003241:Consanguinity; D017931:DNA Primers / Q000235:genetics; D042967:Electron Transport Complex I / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005091:Exons; D005347:Fibroblasts / Q000201:enzymology; D005816:Genetic Complementation Test; D006720:Homozygote; D006801:Humans; D007223:Infant; D007888:Leigh Disease / Q000201:enzymology* / Q000235:genetics*; D008297:Male; D008928:Mitochondria / Q000201:enzymology; D009132:Muscles / Q000201:enzymology; D009154:Mutation; D012333:RNA, Messenger / Q000235:genetics
D017931:DNA Primers; D012333:RNA, Messenger; D042967:Electron Transport Complex I