SMN1 and amyotrophic lateral sclerosis: A significant difference in calreticulin expression was not detected by immunohistochemistry analysis of ALS and WT lumbar spinal cord sections (Figure 5C), but RT-PCR analysis of calreticulin gene expression aligned with the trends seen by western blot results, showing a statistically significant increase in ALS vs. WT (Figure 5D) and a slight, but statistically significant, decrease in SMA vs. control spinal cords (Figure 5E).