Germline DDX41 defines a distinct subgroup in MDS undergoing transplantation with reduced relapse and improved survival.

DDX41

Pathogenic or likely pathogenic germline DDX41 variant, with an additional somatic DDX41 mutation (most often p.R525H) in 39% of carriers

This study analysed 1,514 patients with MDS who underwent allogeneic transplantation before routine DDX41 testing, alongside a wild-type comparator. Forty-nine patients (3.2%) carried a pathogenic or likely pathogenic germline DDX41 variant, 19 of whom (39%) had an additional somatic DDX41 mutation, most commonly p.R525H; carriers were older (median 63 vs 59 years), had lower IPSS-M risk and no TP53 mutations (0% vs 21%). Two-year relapse incidence was lower in carriers (17% vs 34%, p=0.01), with a multivariable relapse hazard ratio of 0.43 (95% CI 0.21-0.88), concentrated in the reduced-intensity/nonmyeloablative stratum. Disease-free survival was improved (HR 0.62; 95% CI 0.41-0.95), with no excess non-relapse mortality or graft-versus-host disease. The authors support incorporating germline DDX41 status into transplant planning.

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

Recruitment before routine DDX41 testing limits selection bias and provides a genuine benchmark, but 49 carriers remain a modest number for stratifying by conditioning intensity. For the geneticist the key step is upstream: identifying the germline variant before transplantation, which also bears on related-donor selection and cascade testing, two points the abstract does not address.

Analysis by Dr Thibaut Benquey