The effects of biological and life-style factors on baseline frequencies of chromosome aberrations in human lymphocytes

Objective: This study investigated the influence of sex and ageing on chromosomal damage and the role of life-style habits on the frequency of chromosomal aberrations (CAs) in peripheral blood lymphocytes (PBLs) of healthy Bosnian subjects. Materials and Methods: Peripheral blood samples were obtained from 100 healthy, unrelated individuals in Bosnia and Herzegovina during 2010 and 2011. Chromosome preparations were made by dropping and air drying and slides were stained with 10% Giemsa solution (pH 6.8). The cytogenetic analysis was carried out in a cytogenetic laboratory in the Department of Biology of the Faculty of Science in Sarajevo. The category of total structural CAs was sub classified as chromosome-type aberrations (CSAs) and chromatid-type aberrations (CTAs) while the category of total numerical CAs was sub classified as aneuploid and polyploid mitoses. All statistical analyses were carried out using Microsoft Excel 2010 (Microsoft Corporation) and the Windows Kwikstat Winks SDA 7.0.2 statistical software package (Texa Soft Cedar Hill, Texas). Results: Cytogenetic analysis revealed the average number of structural CAs was 2.84 and of numerical CAs was 9.56. There was a significant increase in the frequency of chromosome-type aberrations (1.92) compared with chromatid-type aberrations (CTAs) (0.92) and a significant increase in the frequency of aneuploid (8.83) compared with polyploid (0.73) mitoses. Significant positive correlations between age and CTAs in human PBLs were also demonstrated. Additional statistical analysis showed that ageing increase number of numerical CAs in lymphocytes of drinkers. The frequency of structural CAs of females exposed to radiation was significantly greater than in males. Analysis indicates the presence of a positive association between CAs and smoking in younger subjects but a negative correlation between aberrant cells frequencies and alcohol in older drinkers. Conclusion: The results of the study support the conclusion that sex and age, together with life-style habits of individuals as confounding factors can affect spontaneous frequency of CAs especially to CTAs in PBLs that are a biomarker of cancer risk.