Related Experiment Video
Updated: Aug 29, 2025
Characterizing Exon Skipping Efficiency in DMD Patient Samples in Clinical Trials of Antisense Oligonucleotides
Published on: May 7, 2020
Evaluation of Single Exon Deletions in DMD/BMD: Technical and Analytical Concerns
Tavisha Dama1, Pratiksha Chheda1, Shweta Limaye1
1Department of Molecular Pathology, Metropolis Healthcare Ltd., Mumbai, Maharashtra, India.
Background:
Oftentimes, a variation at the multiplex ligation-dependent probe amplification (MLPA) probe binding site leads to improper hybridrization/ligation of the probe showing up as a deletion of an exon leading to false positive results for the detection of Duchenne muscular dystrophy (DMD)/Becker muscular dystrophy (BMD).
Objective:
Investigating cases with single exon deletion using an alternate method [polymerase chain reaction (PCR) or sequencing] for confirmation of the deletion.
Methods:
We evaluated males with single exon deletion (n = 49) in our study population (2015-2019). Forty-six were confirmed by an alternate method (conventional PCR/Sanger's sequencing) to confirm the deletion.
Results:
We observed 25.12% single exon deletions in our study cohort. Further evaluation determined a false positive rate of 6.12%. Three out of 49 single exon deletions had a point mutation near the probe-binding site, indicating a false positive result. Single exon deletions, thus, need to be evaluated with extreme caution, and point mutations, if any, need to be characterized to determine the nature of their pathogenicity.
