Frequency of inversions in the T-lymphocyte chromosomes of exposed residents of the Southern Urals

Abstract

It is well-known that ionizing radiation is among factors increasing the rate of chromosomal rearrangements. The inversion rate was poorly understood due to difficulty of inversion identification by the conventional differential staining method. A comprehensive study of chromatin and its complex rearrangements has become possible with the use of the high-tech molecular genetic method, fluorescence in situ hybridization (FISH). The study was aimed to assess frequency of inversions involving the chromosome telomeric regions in 36 residents of the South Urals, almost all of them were affected by combined chronic exposure. The calculated individualized cumulative external and internal doses were 0.0001–4.7 Gy. Inversions were identified by fluorescence staining of the chromosome telomeric region. It was found that chromatid inversions were more abundant than chromosomal variants (9 : 0.3 per 100 cells (p < 0.001). No relationship between the studied parameters and the absorbed dose, sex and age at the time of the examination was revealed.