Repeat Expansion Detection and Validation

Repeat expansions drive more than 60 neurological and neuromuscular disorders, yet they remain among the most difficult genomic features to study.^1,2 PCR fails on large alleles, while short-read sequencing cannot map across long repetitive tracts because it relies on short molecules and inference.^2,3 Even long-read platforms struggle to span GC-rich expansions at scale, and southern blotting continues to be slow, imprecise, and labor-intensive.³

Existing tools require you to make compromises that leave critical genomic features like repeat expansions only partially resolved. This doesn't just slow down research — it creates gaps in our understanding and highlights the urgent need for new, complementary approaches to see the full picture.

Electronic genome mapping (EGM) overcomes many of the challenges that limit sequencing and legacy methods for repeat expansion analysis. Its unique capabilities deliver advantages in resolution, size detection, and reproducibility across diverse loci and cohorts.

1. Resolution: EGM does not rely on amplification which enables detection of repetitive regions and motifs that are difficult for sequencing.
2. Size: Ultra-long EGM reads enable resolution of normal, premutation, and full mutations and can span even the largest expansions.
3. Reproducibility: End-to-end, the EGM workflow ensures reproducible analysis that can be applied across different loci and study cohorts.

EGM is a whole genome assay and has the potential to screen for up to 30 repeats simultaneously in a single workflow, eliminating the need for multiple locus-specific assays. This comprehensive approach can streamline analysis, reduce turnaround time, and provide consistent resolution across diverse repeat types.