Alternatively, the PCa risk-associated CTCF sites may prevent the promoters of the KCNN3 and KRT78 genes from interacting with a pre-existing active enhancer(s) located outside the loop (in this case, the enhancer would be marked by H3K27Ac in both control and CRISPR-deleted cells). The gene discussed is KCNN3; the disease is posterior cortical atrophy.