CD34 and myelodysplastic syndrome: However, the commonly deleted region (CDR) in del(5q) MDS, which spans 1.5 Mb on band 5q32, only encompasses two of the three microRNAs (miRNAs), miR-143 and miR-145, which are expressed at significantly lower levels in CD34+ cells from del(5q) MDS patients4,6,7.