New genetic test solves mysteries for hundreds of patients with rare disorders

Many families face a long wait for answers when standard genetic tests come back inconclusive. A new review looked at 646 patients with rare genetic disorders who had already received negative or unclear results from standard testing. The team found that long-read whole genome sequencing offered a clear path forward. This advanced method helped 29 individuals receive a definitive diagnosis. That represents a 4.5% success rate among those who previously had no answers. The test also identified different types of genetic changes. Structural variants made up the majority of the findings. Single-nucleotide variants and methylation changes also played a role in solving these cases. The researchers used a standard tool to check for risk of bias. They noted that the results apply specifically to the nine studies included in this review. This approach shows promise for improving diagnostic rates when applied after standard testing.