At Day (D) 42 post-vaccination, we observed an antibody geometric mean concentration (GMC) of 1790.2 milli international units (mIU)/mL for anti-measles, 113.5 enzyme-linked immunosorbent assay (ELISA) units (EU)/mL for anti-mumps, and 76.1 IU/mL for anti-rubella antibodies in the MMR-RIT group (Table 2). The gene discussed is MRC1; the disease is measles.