Nanopore sequencing increases resolution of DMPK hypermethylation in myotonic dystrophy type 1 patients
About Ulf Birkedal
Ulf Birkedal received his Ph.D. in RNA biology and has since been working as a clinical geneticist at Copenhagen University Hospital, Rigshospitalet, Denmark. He is interested in utilising multiple aspects of long-read sequencing for clinical purposes, including transcriptomics, genomic structural variations, and epigenetics.
Myotonic dystrophy type 1 (DM1) is an autosomal dominant multisystem disorder, caused by an unstable expanded CTG repeat in DMPK. Disease progression is partially correlated to repeat length, but also by hypermethylation of CpG sites flanking the expanded repeat. Traditionally, these biomarkers are investigated with different methods. Using Cas9-targeted nanopore sequencing, we simultaneously analysed blood methylation levels, progenitor and modal repeat lengths, somatic instability, and repeat interruptions in four DM1 patients. Allele-specific and single molecule analysis showed the interplay between the repeat expansion and methylation, highlighting the increased resolution using nanopore sequencing for clinical samples.