Radiosensitization of X chromosome of Chinese hamster cells related to incorporation of 5-bromodeoxyuridine.

Selective incorporation of 5-bromodeoxyuridine into the late replicating arm of the X chromosome of Chinese hamister cells cultured in vitro caused a selective radiosensization of the arm to ionizing radiation. Radiation damage was observed as chromosomal aberrations, and incorporation was studied by using tritiated 5-bromodeoxyuridine.