CRISPR/Cas9 Customization of Electronic Genome Mapping Repeat Expansion Assays

Many genetic disorders, including Fragile X syndrome and Friedreich's ataxia, arise from expansions of simple sequence repeats that conventional PCR and sequencing methods cannot size reliably. This work examined whether electronic genome mapping (EGM), made tunable with CRISPR/Cas9, could deliver the accurate, scalable repeat expansion analysis these challenging regions demand.

Using Coriell cell lines, researchers characterized FMR1 (Fragile X syndrome) and FXN (Friedreich's ataxia) repeat expansions with the RepX™ Repeat Expansion Analysis (RepX) pipeline, applying CRISPR/Cas9 to add or remove tag sites and sharpen resolution where tagging patterns were suboptimal. A single OhmX™ Detector with a single sample loading resolved both repeats, including expansions up to ~600 CGG and ~1,200 GAA units—all concordant across replicates.

Explore how CRISPR/Cas9-customized EGM electrifies high-resolution repeat expansion analysis in whole-genome or gene-specific mode.