SLC29A1 and frontotemporal dementia: Furthermore, siRNA-mediated downregulation of SLC29A1 mRNA, but not of SLC29A2 mRNA, which was confirmed by quantitative PCR (Fig. 6D), significantly suppressed FTD incorporation into nuclear DNA upon treatment with 0.5 and 1 μM FTD for 1 hour (Fig. 6E).