Serum samples from four MAR patients displayed positive immunoreactivity with TRPM1 by immunofluorescent labeling of CHO cells transfected with either GFP-tagged human TRPM1 (EGFP-huTRPM1) or GFP-tagged mouse TRPM1 (EGFP-mTRPM1, Fig. 1A). This evidence concerns the gene TRPM1 and myelodysplastic syndrome associated with isolated del(5q).