Furthermore, among other SNPs, the presence of XRCC2 (rs2040639), ATM (rs61915066), TGFB1 (C−509T), PER3 (rs2087947), and PAX7 (rs643644) was significantly linked to an increased risk of developing side effects, such as fibrosis, oedema, fibrosis, telangiectasia, lymphedema, erythema, and desquamation [10,11,12,16,18]. This evidence concerns the gene PER3 and Erythema.