[Age-related dynamics of the genetic marker distribution in an irradiated population. Haptoglobin genetic system]

The age dynamics of haptoglobin (Hp) type and allele distribution was studied in 985 workers aged 35-79 years who worked in the atomic industry. These workers were exposed to chronic radiation in a wide range of doses 17-40 years ago. Along with the chi 2 test, the relative and attributive risks of elimination of Hp types and alleles were determined to obtain the qualitative characteristics of age alterations. The substantial changes in distribution of Hp types and alleles were revealed in individuals older than 60 years. These changes depended on doses of external and internal irradiation. For instance, in individuals of this age group, who received the total dose of gamma-radiation (less than 100 cGy) and or that of plutonium-239 incorporation (less than 1.48 kBq), a decrease in Hp 2-2 and Hp2 and an increase in Hp 1-1 and Hp1 was observed. However, among the individuals of similar age (older than 62 years), who received a higher total dose of external and/or internal radiation, the different Hp type distribution showed a decrease in Hp 2-1 and an increase in Hp 1-1. In the latter case, the changes with age were dose-dependent. In individuals over 60 years of age with essential hypertension or diabetes mellitus and those who had a myocardial infarction, a decrease in Hp 2-2 and Hp2 and an increase in Hp 1-1 and Hp1 were found. This explains the changes with age in individuals irradiated at lower doses. The peculiar changes with age in individuals irradiated at higher doses are possibly due to the difference in morbidity and mortality from malignancy in various Hp type carriers.