What are cell cycle check points?
This is the quality control of the cell cycle. These are points in the cell cycle where the quality of genetic replication is checked. If there are any problems in DNA quality (e.g. mutations) or spindle quality or the presence of Okazaki fragments (these are discontinuous segments of newly formed DNA during DNA replication) the cell is not permitted to proceed in the cell cycle until all of these have disappeared. All these checkpoints require the services of a complex of proteins. Mutations in the genes encoding some of these have been associated with cancer; that is, they are oncogenes. Genes encoding the regulatory proteins include p53, ATM (ataxia telangiectasia mutated), MAD (mitotic arrest defective).
