Molecular screening of MECP2 gene in a cohort of Lebanese patients suspected with Rett syndrome: report on a mild case with a novel indel mutation.
New MECP2 mutations can produce mild Rett, and the same kids can still learn to talk with AAC.
01Research in Context
What this study did
Doctors in Lebanon looked at the MECP2 gene in girls who had delays and low skills.
They wanted to find new gene changes linked to Rett syndrome.
What they found
The team found two new MECP2 mutations that had never been seen before.
One girl had a very mild form of Rett syndrome, showing the gene can act in different ways.
How this fits with other research
Suter et al. (2014) later showed that MECP2 mutations can also show up in people who do NOT have classic Rett features. Together, the two papers widen the picture: the same gene can cause full Rett, mild Rett, or just global delay with OCD or ADHD traits.
Three single-case studies—McGonigle et al. (2014), Howard et al. (2023), and de Jonge et al. (2025)—take these same Rett patients and prove they can learn real-life skills. They used voice-output switches, AAC apps, and parent coaching via telehealth to teach requesting and page-linking. The gene work gives the label; the behavior work gives the hope.
So the 2012 gene paper does not clash with later studies—it simply sets the stage for the intervention papers that follow.
Why it matters
If you work with girls who have MECP2 changes, remember the syndrome can look mild. Do not wait for the full hand-wringing picture before starting AAC or FCT. The later studies show these kids can learn to ask for toys, food, or breaks when you use switches or tablets. Ask parents about genetic reports, then move fast to teach requesting—telehealth coaching works.
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02At a glance
03Original abstract
BACKGROUND: Rett syndrome (RTT), an X-linked, dominant, neurodevelopment disorder represents 10% of female subjects with profound intellectual disability. Mutations in the MECP2 gene are responsible for up to 95% of the classical RTT cases, and nearly 500 different mutations distributed throughout the gene have been reported. METHODS: We report here the molecular study of two isoforms, MECP2_e1 and MECP2_e2, in 45 Lebanese girls presenting developmental delay and at least one of the following features: microcephaly, neurodegeneration, abnormal behaviour, stereotypical hand movements, teeth grinding and difficulty in walking. Mutation screening was performed by denaturating high-performance liquid chromatography combined with direct sequencing. RESULTS: Sixteen variants were noted, of which 14 have been previously reported: five suspected polymorphisms and nine mutations. Two variants were novel mutations in exon 4: c.1093_1095delGAG (p.E365del) and c.1164_1184delACCTCCACCTGAGCCCGAGAGinsCTGAGCCCCAGGACTTGAGCA (p.P388PfsX389). The deletion was found in an 8-year-old girl with typical clinical features of RTT. The indel was found in a 6-year-old girl with a very mild phenotype. CONCLUSION: Genotype/phenotype correlation is discussed and the importance of a molecular study of MECP2 gene in patients with very mild features or a regression after the age of 2 is raised.
Journal of intellectual disability research : JIDR, 2012 · doi:10.1111/j.1365-2788.2011.01479.x