SRRM1 and glioblastoma: Therefore, we performed qRT-PCR on the five healthy and five GBM tissues which we previously sequenced (Table 1) to quantify the expression levels of the known neuronal splicing factor SRRM4 and its family members SRRM3 (neuronal-specific) and the ubiquitously-expressed SRRM1 and SRRM2. Comparing expression by qRT-PCR, SRRM4 was the only family member to be significantly decreased (One-way ANOVA, Mann–Whitney test, p = 0.023) in expression in GBM compared with the normal brain tissue (Figure 3a).