Ubap2l is preferentially expressed in primitive HSCs and AML specimens with high stem cell frequency. (A) Ubap2l mRNA levels in total mouse BM, Lin⁻ cells and primitive HSCs as assessed by qRT-PCR. The values are expressed relative to Gapdh, Tbp, and Hprt. The average of 2 independent experiments is presented with the standard error of the mean. The values for total BM were set to 1. *Statistically significant difference (total BM vs CD150⁺CD48⁻Lin⁻SCA1⁺cKIT⁺: P = .0012). (B) UBAP2L mRNA levels in various human primary AML specimens as determined by RNA sequencing. LSC low refers to AML specimens with low stem cell frequency, and LSC high, to specimens with high stem cell frequency. *Statistically significant difference (P = .0057).