Scientists discover new neurodevelopmental disorder inherited from both parents

Scientists have just identified a previously unknown neurodevelopmental disorder, giving families the diagnosis they've been 'waiting years for'.

Researchers at the University of Bristol shared their findings in a press release on 30 March, after the study was published in the academic journal Nature Genetics.

For context, the term 'neurodevelopmental disorders' (NDDs) refers to disorders that begin in childhood and affect the development and function of the brain.

As per the NHS, they can range from mild impairments, allowing those affected to live fairly normal lives, to severe disorders that require lifelong care.

Examples of NDDs that you may have heard of include attention deficit hyperactivity disorder (ADHD), conduct disorders, cerebral palsy, and impairments in speech and language.

So, researchers think that a whole new one being discovered may bring important answers to the parents of children who have the previously unknown condition, as well as inform future drug development.

The groundbreaking new research will help inform future drug development (Getty Stock Image)

This is about to sound very complicated, but bear with me.

The condition in question is caused by changes in a small noncoding gene called RNU2-2.

It is estimated to affect thousands of individuals and accounts for about 10 percent of all recessive NDD cases with a known genetic cause.

Using the National Genomics Research Library, the researchers analysed genetic data from 14,805 individuals with an NDD and 52,861 without an NDD.

Scientists discovered that the disorder is caused by a near-complete absence of a molecule called U2-2 RNA, which is produced by the RNU2-2 gene.

Children with the condition tend to inherit one altered copy of the gene from each parent, however, sometimes changes can occur spontaneously by genetic mutation.

While the parents are unaffected, the combined effect of both copies of the gene coming together in their children leads to disrupted brain development in the child.

As per Science Alert, the fact that this NDD is both recessive and non-coding explains why it's gone under the radar for so long.

What are the symptoms of the disorder?

The mutation needs to be inherited from both parents to become active (Getty Stock Image)

Symptoms can differ significantly depending on the kid's specific genetic changes, but common signs to look out for include low muscle tone, developmental delays, and limited speech.

Some children may also present mild learning difficulties or autism traits, while others develop epilepsy, movement disorders, or trouble walking.

In the most severe cases, additional challenges may include feeding difficulties or respiratory problems, and brain imaging may appear normal early on but can show changes over time.

Speaking of the groundbreaking research, geneticist and paper co-lead Daniel Greene said: "Our discovery gives families something they've often waited years for, a clear molecular explanation for their child's condition."

He added: "For many families, that clarity can be profoundly meaningful after a long and uncertain diagnostic journey. At the same time, it gives the research community a concrete biological target to guide future therapeutics."

Meanwhile, the study's senior author, Dr Ernest Turro, said: "We are now enrolling families into the INDEED study to diagnose affected individuals, improve our understanding of the natural course of the condition, develop clinical management guidelines, and uncover precisely how U2-2 RNA loss disrupts neurodevelopment.

"We hope these steps will lay a strong foundation for future clinical trials."