POLR2A and amyotrophic lateral sclerosis: Interestingly, the poly-T variant in SCAF4 is flanked by two binding sites for transcription factor RNA polymerase II subunit A (POLR2A); therefore, changes in the length of this variant may influence the binding of POLR2A, thus affecting transcription of nearby genes (SOD1) and may therefore play a role in ALS related neurodegeneration.