Study Examines Insights Gained by Adjunct Trio RNA Sequencing in Complex Pediatric Disease Cases

In the American Journal of Human Genetics, researchers from the Hospital for Sick Children, SickKids Research Institute, the University of Toronto, and elsewhere look at the clinical utility of blood RNA sequencing for diagnosing complex medical conditions, particularly using sequences from parents and affected children who have also been assessed by genome sequencing. Based on findings for 97 individuals from 39 affected families, the team suggests that the addition of blood RNA-seq to genome sequence data can help to clarify splice variant patterns in three of the families, while narrowing the suite of candidate culprit variants that had to be reviewed manually. Even so, the trio RNA-seq approach did not find new causal disease variants missed by genome sequencing, the authors note, and the analysis did not find a significant diagnostic benefit from the approach. "Blood-based RNA-seq can facilitate genome analysis in children with suspected undiagnosed genetic disease," they report, noting that "[i]n contrast to DNA sequencing, the clinical advantages of a trio RNA-seq design may be more limited."