In subgroup analysis, sphincter preservation was significantly higher in patients ≤ 45 years than >45 (76.5% vs. 53.3% respectively, P=0.042), in tumor located >5 cm than ≤ 5 from anal verge (92.3% vs. 47.4% respectively, P=0.0001), and the presence of mucin was associated with less sphincter preservation (40% vs. 70.4%, P=0.003) which was statistically significant, as shown in Table 2. The gene discussed is MUC5AC; the disease is neoplasm.