[Mutation analysis of mitochondrial DNA of children with Rett syndrome].

OBJECTIVE

To identify whether mitochondrial DNA (mtDNA) mutation is involved in the pathogenesis of Rett syndrome (RS), we undertook a mutation analysis of the mtDNA genome.

METHODS

mtDNA from 15 children with RS and 14 their mothers were analysed by using Southern hybridization, polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) and DNA direct sequencing. Total DNA was isolated from white blood cells.

RESULTS

Southern hybridization with whole mtDNA probe revealed no large deletions in mtDNA. PCR amplification and SSCP analysis showed mutation(s) in the region 2650-3000 encoding 16SrRNA of mtDNA in 13 RS patients and 11 their mothers. DNA sequence analysis and mismatch PCR showed a point mutation (C-->T) at the position 2835 in 7 RS patients and 6 their mothers. The same mutation was not found in 30 normal controls.

CONCLUSION

These data indicate that mtDNA may play a role in Rett syndrome.