The most comprehensive study of children who suffer from undiagnosed rare developmental disorders identified 14 new developmental disabilities. The research was conducted at the Wellcome Trust Sanger institute and it also managed to diagnose uncommon developmental issues for more than 1,000 kids and their families.
The study, published Jan. 25 in the journal Nature, allows the families who suffer from the same genetic conditions to connect and access support. The results also accelerate research into the mechanisms of these diseases, as well as possible therapies.
14 New Developmental Disorders Diagnosed
Thousands of children who develop abnormally due to genetic problems are born every year. This situation can lead to a series of conditions such as heart defects, intellectual disability, autism, or epilepsy. There are more than 1,000 recognized genetic causes but there are still a lot of rare individual developmental disorders with unknown genetic causes.
The Deciphering Developmental Disorders (DDD) study is aimed at finding diagnoses for children who suffer from unknown developmental diseases, proving that genomic technologies can improve diagnostic tests.
The research team investigated spontaneous new mutations that occur as DNA is transferred from parents to their children. The kids' conditions were clinically assessed and the team grouped together children who suffered from similar types of disorders to provide diagnoses for their conditions.
The team managed to diagnose kids who had new mutations in genes that are already connected to developmental disorders, in approximately one in every four children in the research. Aside from finding new mutations in already known developmental disorders, the team identified 14 new ones. All the new diseases are caused by the same trigger — spontaneous mutations not found in either of the parents.
According to the research, approximately one in every 300 newborns in the United Kingdom has a rare developmental condition caused by a new mutation in existing developmental disorders, adding up to 2,000 newborns a year in the country.
Another finding of the research was that older parents are at higher risks of giving birth to a child who will suffer from a developmental disorder caused by a new mutation.
"We estimate that 42% of our cohort carry pathogenic DNMs in coding sequences; approximately half of these DNMs disrupt gene function and the remainder result in altered protein function. We estimate that developmental disorders caused by DNMs have an average prevalence of 1 in 213 to 1 in 448 births, depending on parental age," noted the research.
Developmental Disorders, A Threat On Public Health
According to the CDC, developmental disorders occur among Americans as well, regardless of racial, ethnic and socioeconomic factors. According to recent estimates, one in six children aged 3 to 17 years has one or more developmental disorders, among which ADHD, ASD, cerebral palsy, hearing loss, intellectual disability, learning disability, vision impairment, and other developmental delays.
"Most developmental disabilities are thought to be caused by a complex mix of factors. These factors include genetics; parental health and behaviors (such as smoking and drinking) during pregnancy; complications during birth; infections the mother might have during pregnancy or the baby might have very early in life; and exposure of the mother or child to high levels of environmental toxins, such as lead," noted the CDC website.