The experience of mutation rate quantitative evaluation in connection with environmental pollution (based on studies of congenital anomalies in human populations)

Abstract

For 3 years genetic monitoring of congenital anomalies (CA) has been carried out in three Ukrainian towns essentially different in the level of air pollution: the most polluted, Mariupol (M.); medium polluted, Zaporozhye (Z.); and relatively clean, Simpheropol (S.). In this work we present the results of this study. Eighteen CAs being used in the International Clearinghouse program were registered during the first year of life. For each case of CA an individual questionnaire was filled in. It included practically all known causes of malformations. Similar questionnaires were filled in for cases of normal birth outcome. The estimation of newborns of control groups was made according to a score of 9-10 on the Apgar scale. The questionnaires were completed by physicians in all maternity hospitals and children's clinics and based on the information obtained from mothers. Multiple malformations, dominant and X-linked CA in M. were 2.6-3.1 times more frequent than in S. The frequency of new mutations was 0.45-0.95 and 0.17-0.47 per 10(3) births respectively. No differences in multifactorial and recessive CA were noted. The mathematical method (so-called statusmetrical analysis) was used to indirectly determine the part of CAs of unknown etiology (probably of mutation origin) in the total number of CAs. Their quota in Z. and M. was 1.2-1.5 times more than in S. The advantage of statusmetrical analysis lies in the absence of any restrictions connected with a large number of parameters which describe the object's status. It makes it possible to analyze tens, even hundreds of factors (along with the increased number of parameters the reliability of the conclusions increases) and range them in accordance with their validity. Genetic consequences of chemical pollution were estimated in biological equivalents Röntgen (BER). In M. they were equal to the effect of irradiation at doses of 180-300 BER (230 BER, central estimate) over 30 years. In the polluted towns (M. and Z.) the relation between average annual general emission of atmospheric pollutants (M./Z.) was 2.21, the frequency of dominant and X-linked CA 2.20 and of new skeleton mutations 2.24. The difference of mutation rate in the towns studied was due to the dynamics of demographic processes.