BACKGROUND

Rett syndrome (RTT) is a severe, progressive, neurodevelopmental disorder predominantly observed in females that leads to intellectual disability. Mutations and gross rearrangements in MECP2 account for a large proportion of cases with RTT. A limited number of twin pairs with RTT have also been reported in literature.

CASE PRESENTATION

We investigated 13 year old, monozygotic twin females with RTT and some noticeable differences in development using a combinatorial approach of sequencing and Taqman assay. Monozygosity status of the twins was confirmed by informative microsatellite markers.

CONCLUSIONS

The twins shared a de novo deletion in exon 3 in the MBD domain of MECP2. To the best of our knowledge, this is only the second report of genetic analysis of a monozygotic twin pair.