Spotting the signs


If you’re reading this article, the chances are you know what Rett Syndrome is. But could you spot it in a young child? In the UK, there are far less children and adults identified with Rett Syndrome than there should be. With treatments on the horizon, this needs to change.

But finding children and adults with Rett Syndrome within the UK isn’t easy. Currently there is no quick, accurate and inexpensive way to check whether someone has mutations in the MECP2 gene.

Testing is not triggered by any particular criteria within the NHS and the process is lengthy, with a recent survey conducted by Reverse Rett showing that test results have taken over 6 months to come back for 55% of young patients diagnosed with Rett Syndrome in the last five years. 

Spot the signs

To mark Rett Syndrome Awareness month, we’re sending a targeted mailout and ‘spotting the signs’ leaflet to all 650 MPs in partnership with CoreMarketing. The email calls for each MP to share the leaflet with their GPs, hospitals, sports centres and meeting places. We need everyone to know what the signs of Rett Syndrome in young children are, so that families, caregivers and supporting professionals can request MECP2 testing and a confirmed clinical diagnosis as soon as possible.

Issues around genetic testing

The lack of a formalised trigger for MECP2 testing and subsequent delayed return of test results in young children with Rett Syndrome is damaging to the children and families who may not be able to access adequate or appropriate therapies, supports and services in the time they are waiting for test results.

But with treatments and cures for Rett Syndrome looming, it is now more important than ever that we establish a genetic testing pathway so that young children with Rett Syndrome can be identified and registered quickly, giving them the best possible chance to access treatment at any early age.

At Reverse Rett, we are working with industry partners and other genetic CNS rare disease groups to highlight our priorities with regards to diagnostic testing and to look for avenues for collaboration. 

We’re also these highlighting issues around genetic testing in Rett Syndrome and the critical need for earlier and more effective diagnostic tools through Reverse Rett participation in the Cambridge Rare Disease Network Rare Summit 2021 on October 7th, where our poster and video presentation about Rett Syndrome will be on display. 

A summary of the issues we face in three distinct groups of patients; young children, adult women and baby boys with Rett Syndrome.

Young children

Current issues:

●      There is no identified bio marker in the blood or urine that could indicate Rett Syndrome.

●      There is a DNA sequencing test for Rett Syndrome which is not routinely provided to young children presenting with global developmental delay in the UK.

●      There is no established ‘trigger’ for testing within the NHS for this patient group; i.e. young female, developmental delay, decelerated head growth, unusual hand movements, lack of speech and or mobility.

●      Testing is often initiated by parents; many under-represented and or disadvantaged groups are missed or not listened to.

●      Target reporting time is 8 weeks. A recent survey by Reverse Rett showed that test results took over 6 months to come back for 55% of patients diagnosed in the last 5 years.

●      Children are deteriorating un-necessarily without access to an enriched environment which can be provided through access to existing services. 


Current issues:

●      The gene for Rett Syndrome was identified in 1999. Many adult patients who were clinically diagnosed before 1999 do not have confirmed genetic results and will therefore be technically ineligible for Gene Replacement Therapies.

●      Many adult patients with Rett Syndrome will be undiagnosed and will therefore not be able to access gene therapy and or other treatments. Since genetic testing has become available, many patients who would typically not have met clinical criteria for classic Rett Syndrome, have been identified.

●      There is a ‘throw-away’ attitude about adult patients who have lived with severe disabilities for life with regards to expensive genetic testing. A positive MECP2 test for an adult patient with Rett Syndrome, could provide access to both existing and emerging treatments which could significantly improve the lives of these patients and diminish the burdensome costs associated with long-term 24 hour care.

Baby boys

Rett Syndrome is most often associated with little girls as it is an X-linked disorder.

Males can be affected, typically more severely than females, at an earlier age.

Current issues:

●      The few baby boys who have been correctly diagnosed with Rett Syndrome in the UK in the last five years, have been diagnosed through Whole Genome Sequencing when they are already severely ill, in several cases, days from death.

●      There is no established ‘trigger’ for MECP2 testing within the NHS for this patient group. i.e. young male with seizures, hypotonia, respiratory compromise, immune problems.

●      These children are deteriorating and often dying without clinicians having access to critical and potentially life saving information about their condition because they are not accurately diagnosed until it is too late.

●      A fast and effective MECP2 test for young males who may potentially have Rett Syndrome could provide access to, not just life-changing, but life-saving gene therapy treatment.

In summary:

In the UK, there is no established route to a fast and accurate diagnosis for either:

●      female toddlers

●      baby boys

●      adults

with Rett Syndrome

which will be a barrier to accessing treatment when gene therapy and other life changing treatment becomes available for these patients. 

Rett Registry UK

Despite the challenges we face, we do have a strong national patient registry, the Rett Registry UK.

Once individuals are identified as having either an MECP2 mutation or a clinical diagnosis of Rett Syndrome or both, we need families and caregivers to register their loved one on the Rett Registry UK.

The new app version of the Rett Registry UK will launch later this month. If you are already registered, you will receive an invitation at that time. If you are not registered, follow the link below to register today.

This is critical in the effort to drive treatments and a cure for Rett Syndrome forward for everyone living with Rett Syndrome today. Thank you.



 2. Downs, J., Rodger, J., Li, C. et al. Environmental enrichment intervention for Rett syndrome: an individually randomised stepped wedge trial. Orphanet J Rare Dis 13, 3 (2018).

 3. Amir, R. E., Van den Veyver, I. B., Wan, M., Tran, C. Q., Francke, U., & Zoghbi, H. Y. (1999). Rett syndrome is caused by mutations in X-linked MECP2. Nature Genetics, Oct;23(2), 185–188.