Regarding the other DNA repair pathways, we analyzed DNA repair-related gene expression in FACS-sorted tubular epithelia; parp1, parp2, xrcc1 and aptx for SSB repair, xrcc2 and xrcc3 for homologous recombination (HR), and fancd2 and bcra2 for the Fanconi anemia (FA) pathway (Fig. 6e). This evidence concerns the gene APTX and Fanconi anemia.