Intrinsic radio-sensitivity of tumours to low let radiations: a mathematical model in LQ formalism.

Intrinsic radio-sensitivity is the determinant of differential response of tumours to low LET ionising radiations. The probabilistic DNA fibril both model shows intrinsic radio-sensitivity factor [I] as function of nuclear diameter (Nd) and intra cellular hydrogen ion concentration [H+]. Linking probabilities of lethal and sub-lethal events to [I] further results in equations which show the LQ parameters namely alpha and beta are functions of (Nd), [H+] and repair constant (µ) mu. This model is able to explain radiobiological phenomena of OER and Do value of lymphocytes.