[Mutational analysis of the MECP2 gene by direct sequencing in Hungarian patients with Rett syndrome].

INTRODUCTION

Rett syndrome is an X-linked neurodevelopmental disorder characterized by loss of acquired skills and stereotypical hand movements. Mutations in the gene encoding methyl-CpG-binding protein 2 have been identified as cause of Rett syndrome in 1999.

AIM: The authors initialized mutation screening of this gene in Hungarian patients identified on the base of clinical manifestation in various institutes. So far 25 patients were examined who were supposed to have Rett syndrome.

METHOD: Total genomic DNA was extracted from peripheral blood with routine desalting method for mutation analysis. The three coding regions of the gene were amplified with primer pairs described. The PCR products were analysed by direct sequencing.

RESULTS

Mutations in methyl-CpG-binding protein 2 gene were found in 17/25 cases (68%). This rate of mutation among Rett patients corresponds well with the findings of other studies. Two novel mutations were found. In the first patient whose history was characterized by a slower than normal progression, a G insertion at the base position 276 of exon 3 was detected, while in the second child a double deletion (191, and 9 bases, resp.) in exon 4 was identified.