For example, the identification of BRCA1 and BRCA2 mutations in breast cancer, mutL homolog 1, mutS homolog 6, and mutS homolog 6 mutations in colon cancer, and the RB1 mutation in retinoblastoma is useful for understanding cancer progression in relation to different prognoses and treatments [226,227,228]. The gene discussed is BRCA2; the disease is cancer.