CHEK2 and Li-Fraumeni syndrome: After that, although the possibility of CHEK2's contribution to LFS and Li–Fraumeni syndrome-like (LFS-L) has been inferred by many researchers, there was no evidence indicating CHEK2 is a major gene involved in LFS and LFS-L.[11–20] To date, 4 mutations in CHEK2 have been reported to be associated with LFS or LFS-L: c.1100delC frameshift mutation, c.470T>C nonsynonymous mutation, c.1422delT frameshift deletion, and c.983T>C nonsynonymous mutation,[11,14,15,20] which confirms the relationship between CHEK2 and LFS.