CHEK2 and Li-Fraumeni syndrome: More recently, common mutations in CHEK2, such as 1100delC, I157T and IVS2 + 1G > A, have been associated with different types of cancer [15-17], but the association of CHEK2 mutations with Li-Fraumeni syndrome has been questioned because of different phenotypes in Li-Fraumeni patients and CHEK2 mutation carriers [18].