On a molecular level, they often share mutations in different genes, such as KRAS, BRAF, PTEN, PIK3CA, ARID1A, ERBB2, CTNNB1 and PPP2R1A. Type II ovarian carcinomas mainly cover high-grade serous carcinomas and are more frequent, as they represent approximately 75% of all ovarian carcinomas. This evidence concerns the gene ARID1A and ovarian carcinoma.