Unraveling missing variants through target capture-based long-read sequencing in autosomal recessive disorders.

Target-capture long-read sequencing (56 genes) uncovering SVs, deep intronic variants and allele phasing missed by short-read.

Target-capture long-read sequencing (LRS) covering 56 genes, applied retrospectively to 78 patients suspected of autosomal recessive disease who remained undiagnosed after short-read (SRS) with a single pathogenic allele detected. Functional validation by RT-PCR and minigene refined pathogenicity. LRS solved 25.6 % of cases (20/78) by identifying 10 structural variants, 3 deep intronic variants confirmed to disrupt splicing, and 7 cases where phasing confirmed the trans position, reclassifying VUS as likely pathogenic. The authors honestly note that this yield applies to an enriched population and should not be extrapolated to unselected cohorts.

Synthesis written by Geno'X. For the full original abstract, please refer to the source publication.

A pragmatic, well-framed use of long-read sequencing: targeting single-allele recessive cases, where short-read struggles with SVs, deep intronic variants and phasing. The trans phasing that reclassifies VUS is particularly useful in routine practice. The transparency about cohort enrichment (not to be extrapolated) is welcome and rare — an honest methodological point.

Analysis by Dr Thibaut Benquey