A pilot study has identified potentially disease-causing mutations in hematopoietic stem cells from young healthy donors that were transferred to unrelated transplant recipients, suggesting that such mutations are more common in people under 50 years of age than previously thought. A team led by scientists from Washington University School of Medicine performed error-corrected sequencing on 125 blood and marrow samples from 25 matched unrelated donors and recipients. Eleven of the donors — who had a median age of 26 — had clonal mutations that couldn't be detected with standard sequencing techniques, with 84 percent of the mutations predicted to be pathogenic. Notably, 100 percent of the mutations engrafted in recipients, and the clones expanded in these patients in the first 100 days after transplantation. The findings, the investigators write in Science Translational Medicine, suggest that rare, pathogenic clonal mutations are far more prevalent in younger adults than previously appreciated, and point to the need for larger studies with longer follow-up periods to correlate clonal engraftment with post-hematopoietic stem cell transplantation morbidity. GenomeWeb has more on this, here.
A genome-wide association study appearing this week in Science Advances indicates that heavy alcohol consumption can increase an individual's risk of lung cancer and other conditions. A University of Liverpool-led team examined data on roughly 125,000 individuals from the UK Biobank to determine genetic factors associated with extreme population-level alcohol consumption, identifying six loci attaining genome-wide significant association with alcohol consumption. The findings were replicated using data on nearly 48,000 people from Kaiser Permanente's Genetic Epidemiology Research on Adult Health and Aging cohort, while experiments in nematodes showed a conserved role in phenotypic responses to alcohol for all genetic targets available for investigation. Evidence of causal links to lung cancer, and shared genetic architecture with gout and hypertension, was also found. The scientists note, however, that additional study is required to "realize the potential of these outcomes and result in meaningful population- or clinical-level impact." GenomeWeb also covers this study, here.