CLEC10A and amyotrophic lateral sclerosis: There is a significant increase in HERV-K pol expression in cortical brain tissue from patients with ALS compared with non-ALS controls.41 HERV-K pol levels from the HML-2 and HML-3 subfamilies differ across brain regions in patients with ALS but not in the non-ALS controls, as do the genomic loci where the transcripts originate, suggesting unique patterns of expression in the brains of those with ALS.