Medically relevant tandem repeats in nanopore sequencing of control cohorts

Research and diagnostics for medically relevant tandem repeats and repeat expansions are hampered by the lack of population-scale databases. We attempt to fill this gap using our pathSTR web tool, which leverages long-read sequencing of large cohorts to determine repeat length and sequence composition in the general population. The current version includes 878 individuals of the 1000 Genomes Project cohort sequenced on the Oxford Nanopore Technologies PromethION. A comprehensive set of medically relevant tandem repeats were genotyped using STRdust to determine the tandem repeat length and sequence composition. PathSTR provides rich visualizations of this dataset, as well as the feature to upload one’s own data for comparison along the control cohort. We demonstrate the implementation of this application using data from targeted nanopore sequencing of a patient with Myotonic Dystrophy type 1. This resource will empower the genetics community to get a more complete overview of normal variation in tandem repeat length and sequence composition, and enable a better assessment of the pathogenic impact of tandem repeats observed in patients. PathSTR is available at https://pathstr.bioinf.be