Through DNA sequencing, a new study has uncovered genetic causes for certain developmental delays. Finding the underlying reason for these delays then allowed treatments to be specifically targeted to 44% of the affected individuals.
Many children, especially those born prematurely, often have delays in their development. They may not walk, talk or reach milestones during the time frames that are typical for children in their age group. Others suffer from intellectual disabilities. These lags are collectively referred to as developmental delays.
In many cases, the underlying cause of a developmental delay is not known. But, there are 90 types of inborn errors of metabolism (inherited disorders where the body cannot properly turn food into energy) associated with intellectual disabilities, which are treatable. In this study published in the New England Journal of Medicine, researchers from the University of British Columbia in Canada sought to see if other metabolic disorders might be discovered.
First, the researchers identified individuals with developmental delays and intellectual disabilites that were caused by metabolic problems. They then screened for and ruled out the 90 metabolic diseases known to cause intellectual delays, and tested the DNA of the remaining participants.
The results? Seventeen of the 41 individuals were diagnosed with conditions which enabled them to receive a targeted change in their treatment options. Treatments included specific diets, medications or supplements. In a few of the study participants, the results of the new treatments were substantial – – improving attention, communication and seizure control.
March of Dimes Chief Medical Office Dr. Edward McCabe commented “there are a number of specialized centers taking a DNA sequencing approach to identify the causes of diseases in patients where the cause had remained unknown. Clinicians are learning who has the expertise.”
The bottom line
As DNA sequencing becomes more accessible, it is hoped that children with developmental delays, and especially intellectual disabilities, will be able to receive targeted interventions earlier, which in some cases can dramatically change the course of their condition.
“This is the way medicine will be practiced and it’s important for us to recognize there are a lot of genes for which we haven’t identified a disease association,” adds Dr. McCabe. “Using sequencing, we can get a precise diagnosis on an individual where there was none prior.”
See our info on Delays and Disabilities – How to get help for your child.