A number of human cancers are sensitive to mitotic stress, implying checkpoint defects. Many proteins that contain forkhead-associated (FHA) domains are cell cycle checkpoints and CHFR is one such protein. It has a FHA and ring finger domain within its N terminus. Within its C terminus, CHFR contains a cysteine-rich region that did not display significant similarity to any protein in the GenBank database, but is highly conserved between humans and mice. It has been concluded that CHFR defines a checkpoint that delays entry into metaphase in response to mitotic stress. It has been found CpG methylation-dependent silencing of CHFR expression occurs in 45% of cancer cell lines, 40% of primary colorectal cancers, 53% of colorectal adenomas, and 30% of primary head and neck cancers.