XRCC1 and squamous cell carcinoma: In an analysis by Pratesi et al. [9] involving data of 101 patients with squamous cell carcinoma HNC, intense dysphagia and acute mucosal reaction after radiation occurred more frequently in patients with polymorphisms of genes XRCC1 c.1196A > G (allele A) and RAD51 c.-3429 G > C (allele C).