Myelodysplasia gene mutation can aid diagnosis
The recent discovery of gene mutations in a genomic study of myelodysplastic syndromes could enable diagnosis using only a blood test rather than a bone marrow biopsy, and could lead to improved treatment protocols.
A diverse and common group of chronic hematologic cancers, the myelodysplastic syndromes are characterized by low blood counts (most commonly anemia) and a risk of progression to acute myeloid leukemia. Dr. Elli Papaemmanuil of the Welcome Trust Sanger Institute in Hinxton, Cambridge, United Kingdom, and colleagues used sequencing technology to identify mutations in patients with low-grade myelodysplasia.
The investigators learned that the SF3B1 gene was frequently mutated in myelodysplasia, one of the most common forms of blood cancer and particularly prevalent in persons older than 60 years. Because anemia is often the only symptom of the disease, making a positive diagnosis can be challenging. Patients with SF3B1 gene mutations frequently displayed a specific abnormality of red blood cells in their bone marrow, called ring sideroblasts.
SF3B1 mutations were found in 72 of 354 patients (20%) with myelodysplastic syndromes, with particularly high frequency among those whose disease was characterized by ring sideroblasts. The gene was also found to be mutated in up to 5% of patients with various other tumor types. Clinically, patients with SF3B1 mutations had fewer cytopenias and longer event-free survival than did patients without such mutations.
Although bone marrow samples are required to detect ring sideroblasts, the SF3B1 mutations can be identified in peripheral-blood DNA.
Papaemmanuil's team speculated in The New England Journal of Medicine (http://www.nejm.org/doi/pdf/10.1056/NEJMoa1103283) that identifying patients who have myelodysplastic syndromes with a benign prognosis may be feasible on the basis of screening for SF3B1 mutations using a single blood sample rather than by means of an invasive and painful bone marrow biopsy.