Long-Read Sequencing Technology to Identify Genetic Contributors of Rare Diseases in Children

As genetic sequencing technology advances and becomes more accessible, significant progress has been made in understanding the genetic bases of various diseases. This progress has sparked a proliferation of clinical applications for genetic testing, providing hope and better outcomes for individuals suffering from numerous genetic conditions. Despite these advancements, there remains a significant number of individuals with rare diseases who go undiagnosed, even with cutting-edge genomic testing. To address this, a team of researchers is now employing a novel sequencing approach known as long-read genome sequencing to re-examine the genomes of individuals who previously underwent sequencing without receiving a diagnosis. Long-read sequencing offers a more complete view of the genome, capturing many genetic variants that may be overlooked by traditional sequencing techniques.

At the HudsonAlpha Institute for Biotechnology (Huntsville, AL, USA), researchers are leading the way in using genome sequencing to transform the diagnosis of genetic disorders, particularly in children. Since 2013, the team has sequenced the genomes of nearly 2,000 children, with over 40% revealing genetic insights related to their clinical symptoms. They are now focusing on long-read sequencing, which they believe could provide diagnoses for more children and their families. Preliminary findings indicate that long-read sequencing could identify significant genetic insights in 5-10% of cases previously tested but undiagnosed, potentially improving diagnostic rates for a broad spectrum of pediatric conditions. Given that this technology is still in its early stages, there is considerable scope for further refinement and improvement, which could even further enhance diagnostic success rates as indicated by initial studies.

Image: The researchers have been awarded an NIH grant to identify genetic contributors to rare diseases in children (Photo courtesy of Adobe Stock)

The research team plans to apply long-read sequencing to re-assess the genomes of over 500 individuals whose previous short-read sequencing did not yield conclusive results. In certain cases, they will also sequence the genomes of the patients' parents to detect both inherited and new genetic variations. Long-read sequencing is particularly adept at identifying types of genetic variations that are not typically detected with short-read sequencing, such as structural variants. These structural variants, which include large deletions, duplications, inversions, translocations, and other complex rearrangements, can disrupt gene function and lead to disease. The limited capability of short-read sequencing to detect these structural variants means that long-read sequencing may uncover additional variants that could explain the symptoms in some patients.

“Long-read sequencing holds immense promise for uncovering the genetic causes of diseases,” said HudsonAlpha Faculty Investigator Greg Cooper, PhD. “My team and I are passionate about making a difference in the lives of individuals and families affected by rare genetic disorders. By pushing the boundaries of genetic research, we hope to shed light on previously hidden genetic variation and provide more accurate and timely diagnoses. Our goal is to empower families with the knowledge they need to navigate their health challenges and build a better future.”

Related Links:
HudsonAlpha Institute for Biotechnology