Hagar Mor-Shaked from the Hadassah Medical Organization & Faculty of Medicine at the Hebrew University of Jerusalem in Israel presented at London Calling 2023 on “Pathological short tandem repeats analysis by long-read sequencing in affected individuals.” They explained that pathological repeat expansions can be found in coding and non-coding regions, and a few dozen have been identified. Their nature makes it difficult to identify, and repeat-primed PCR and shot-reads whole genome sequencing have been used. If there is a clinical suspicion, PCR would be performed for a single test. As a proof-of-concept, Mor-Shaked and the team looked at nine repeat expansions using long-read sequencing. The software they developed identified reads and plots pathological short tandem repeats in individuals. This proof-of-concept test indicated that long-read sequencing with Oxford Nanopore can be used to reliably determine repeat expansion regions. Read depth made a difference, and plots were created comparing normal/healthy and mutation sites. In the future, the team hopes to create a single test to identify and analyze several sites. The software can be used and updated with new loci.
