Figure 1.

A novel mosaic variant of MECP2 in a male patient with typical Rett syndrome. Electropherogram shows the nonsense variant in exon 1 of MECP2 [NM_001110792.1: c.31G>T: p.(Gly11*)] in mosaicism (a). Dde I digestion of the PCR product encompassing the variation site shows additional fragments (143 and 215 bp), which resulted from the G‐to‐T transition creating a new Dde I restriction site in the patient but not in his parents (b). These additional fragments are observed together with the 358 bp wild‐type fragment, confirming the mosaic variant in the patient