Random frequency of radiation induced aberrations in individual chromosomes of lymphocytes of α -thalassemia variant patients

Abstract

Abstract To evaluate the effects of ionizing radiation on chromosomal aberration in lymphocytes of α-thalassemia variants compared to normal controls, venous blood samples were obtained from 10 healthy volunteers and 30 α-thalassemia patients. Different types of α-thalassemia were diagnosed by multiplex polymerase chain reaction. Blood samples were divided into two parts, the first exposed to 3 Gy gamma rays generated from a 60Co source and the other without any irradiation. The blood samples were used for preparation of metaphase cells according to standard methods. Results showed that the frequency of spontaneous aberration (about 0.012 per cell) was similar in all study groups. Irradiated samples showed significantly higher frequency of aberrations (about 0.6 per cell) compared to non-irradiated samples in all groups but similar for control and α-thalassemia variants. The frequency of dicentric chromosomes was significantly higher than other aberrations. In normal individuals in all of the chromosomes except in chromosome 1, a random distribution of break points proportional to their length based on their DNA content was observed. In α-thalassemia variant individuals in all of the chromosomes, a random distribution of break points proportional to their length based on their DNA content was observed.