Figure 4. Biallelic expression of PPP1R9A in prostate benign and cancer tissues. Heterozygosity at the SNP rs854544 in the coding sequence of PPP1R9A was determined by SNP pyrosequencing analysis using genomic DNA (gDNA). Biallelic expression of the gene is evident from the presence of two peaks for the polymorphism A/G, as examined by pyrosequencing analysis of PCR products using cDNA as a template from benign (“pN”s in upper panel) and tumor (“pTu”s in lower panel) heterozygous samples.