Rethinking Seizure Care Blog

Analyzing Genetic Diagnostics of Neurodevelopmental Disorders with Epilepsy in Adults

Posted by RSC Diagnostics on May 21, 2021

DNA molecule is located in front of a colored background. abstract collage

Typically, genetic diagnostics of neurodevelopmental disorders with epilepsy (NDDE) focus on children. This means there is a dearth of data when it comes to adult patients with epilepsy. However, a study that was recently published in Genetics in Medicine looked at the genetic associations of NDDE in adults, as well as elderly patients.

How Did The Study Work?

The researchers had 150 patients with NDDE go through traditional karyotyping, as well as chromosomal microarray, FMR1 testing, and panel sequencing. When there were remaining unsolved cases, they had exome sequencing performed. In 71 of the patients, the researchers found likely pathogenic variants.

In most of the cases, they found that there were mainly “single-nucleotide variants, with 23 cases of disease-causing copy number and one case of fragile X syndrome.” In seven of the patients, they identified multiple independent genetic diagnoses. The researchers observed an association “between diagnostic yield and severity of intellectual disability.”

In the case of patients that had potentially related events early in their life that couldn’t conclusively be connected to their disorder, the yield was 58.3%. The information that the researchers learned about the patients showed that successful phenotyping could provide doctors with a lot more data.

In 32 of 71 patients who had an NDDE diagnosis, it was found that there should be a more detailed evaluation when it comes to the specific comorbidities. This “involved screening for disease-associated malformations and/or cardiac arrhythmias and/or potential tumor predispositions that had previously been associated with the respective disorder—even if the individual evidence remained low.”

The researchers found that their diagnostic yield of 47.3% is much higher than what was found with previously published studies. In other studies, around 23% of the panel-based approaches focused mainly on SNVs and disregarded CNVs.

The researchers found that the panel/exome sequencing had the highest yield and should be considered as first-tier diagnostics for NDDE. Additionally, it will be capable of detecting most alterations that are typically revealed with conventional genetic testing methods including CMA and cytogenetic karyotyping.

Why Epilepsy Research is Difficult

Although there is more research on epilepsy today than there has been in the past, researchers are still trying to get a good handle on the disease. It is hard to research because it is difficult to pin down. There aren’t just one or two types of epilepsy. There are many, and it can affect people differently. There are forms of epilepsy that are found in children, epilepsy in adults, seizures caused by accidents, etc. Therefore, there need to be multiple areas of research, all of which can chip away at the mystery of epilepsy. The goals are to get a better understanding of the disease and the way it manifests and to find better ways to treat patients and provide them with the help they need. Genetic testing of adults who have NDDE is an important aspect of this research.

Why Studying Adult and Elderly Patients With NDDE is Important

As mentioned earlier, the research on adult and elderly patients in this particular area is limited. The researchers who conducted the study believe that genetic testing of individuals with NDDE can have a “direct implication on therapy—even in adult and elderly patients.” As more and more evidence on the approaches that are being used and implemented by researchers and doctors is gathered, it could mean that more patients will be able to benefit from the successes. The researchers encourage clinicians to consider genetic testing with their adult and elderly patients. It could help them find better, workable treatments that could work well for them.



Topics: Epilepsy Studies