KRAS and urinary bladder carcinoma: In contrast, Schistosoma stimulates the onset of bladder carcinoma most likely through mutation in the KRAS gene (Kirsten rat sarcoma viral oncogene homolog), which is one of the three proto-oncogenes encompassed in ras group, inlcuding HRAS (Harvey rat sarcoma viral oncogene homolog) and NRAS (Neuroblastoma RAS viral (v-ras) oncogene homologs).