Radiation sensitivity of human lymphocytes

A simple and rapid in vitro technique to assess the sensitivity of human lymphocytes to X- and UV-radiation is described. Peripheral blood lymphocytes are cloned in agar and colony survival is used as the end point. Survival down to a fraction of approx. 0.02 can be measured accurately. The D10 for X-radiation is approx. 165 rad and the initial portion of the survival curve is linear with no evidence of a threshold. The D10 for UV-radiation is approx. 50 erg/mm2. The technique should be of value both for general radiobiological studies and for detecting individuals having abnormalities of DNA repair.