- SB3F1 is a RNA splicesome, mutated SB3F1 may result in an alternative function proteins instead of a loss of function mutation (Obeng, et al.)
- Point mutations associated with MDS are in the regions of exons 14 to 16
- ~25% of all cases of MDS have a SB3F1 mutation
- ~80% of MDS-RS SLD have SBF3F1 mutation
- 30-70% of MDS-RS MLD have SB3F1 mutation
- 20% of MDS/MPN cases have SB3F1 mutation
- Heterozygous mutation of SB3F1 mutation is associated with disease
- Obeng et al. demonstrated in mice that an isolated SB3F1 mutation is sufficient to cause MDS-type findings
- The presence of a SB3F1 mutation has a positive predictive value (PPV) of finding ring sideroblasts of 97.7%.
Tag Archives: MDS-RS
Ring Sideroblasts
Definition
- ≥5 iron staining granules (+)
- Encircling at least 1/3 of the nucleus
Diagnostic criteria for significant in MDS are ≥15% ring sideroblasts without evidence (or knowledge) of a SB3F1 mutation. This threshold drops to ≥5% with a SB3F1 mutation) Continue reading Ring Sideroblasts
MDS-RS (SLD & MLD)
Myelodysplastic Syndrome with Ring Sideroblasts (MDS-RS)
2016 WHO revision effectively replaces the category of refractory anemia with ringed sideroblasts (RARS) as MDS-RS with single lineage dysplasia (MDS-RS-SLD), and is expanded to include cases of MDS with ring sideroblasts and multilineage dysaplasia (MDS-RS-MLD). Continue reading MDS-RS (SLD & MLD)