Influence of solar activity and geographic latitude on genetic homeostasis of human somatic cells.

AIM: is to determine the effect of solar activity on the genetic stability of human somatic cells as assessed by the micronucleus test in buccal epithelium, depending on the geographical location of the subjects. METHODS: The subjects were men aged 18 to 21 years, without bad habits, who have not taken any medication recently. Studies were conducted simultaneously in four cities of the Russian Federation (Voronezh, Sevastopol, Tomsk, Khanty-Mansiysk). The effect of three types of solar flares, whose classification is based on changes in the amplitude of the thermal X-ray burst, was studied. Material for cytogenetic study was collected on days 3, 7, and 10 after the solar flare. The human buccal epithelium micronucleus test was chosen as a method to evaluate genetic homeostasis. 495 thousand buccal epithelial cells were analyzed. Statistical processing of the study results was performed using "Stadia" and "Statistica" software packages. Identification of the influence of factors was performed using multivariate analysis of variance and two-factor analysis of variance with fixed effects. RESULTS: It was revealed that solar activity affects the stability of the human genetic apparatus by increasing the influence of the city pollution and its geographical location on the number of cells with nucleus abnormalities. The combined effect of solar flare and season of its occurrence on the number of cells with nucleus aberrations (the highest number of nuclear anomalies was registered in winter) was shown. No independent influence of solar activity on the number of cells with nuclear abnormalities was revealed. Thus, 3, 7, 10, and 17 days after the flare, no increase in the number of cells with nucleus anomalies was registered. CONCLUSION: The highest number of cells with nucleus abnormalities is observed in Sevastopol, which is associated with the highest anthropogenic pollution of this city compared to the other cities. Solar activity increases the influence of the city pollution and its geographical location on the number of cells with nucleus abnormalities. The results obtained can be used in conducting a micronucleus test of human buccal epithelium and in planning measures to assess the genotoxicity of the environment.