[A medico-genetic study of isolates in Uzbekistan. III. Results of a cytogenetic study]. / Mediko-geneticheskoe izuchenie izoliatov v Uzbekistane. III. Rezul'taty tsitogeneticheskogo obsledovaniia

The cytogenetic examination of the population of the villages of Karakent and Ishan consisted of two directions: the study on the frequency of chromosome aberrations in the culture of lymphocytes and the diagnostics of anomalies and variants of karyotype. The frequency of chromosome aberrations of 40 individuals was studied. It is shown that the frequency of cells with chromosome aberrations of the individuals in different villages does not differ and on the average is 1,4%. The distribution of lymphocyte culture according to the number of aberrations corresponds to that of theoretical Puassonian. Chromatide breaks are the main type of the aberrations. Among 250 karyotypically examined individuals no evident structure reformations were found. In the caryotype of a 7-year old girl trisomia of the 21st autosome was detected. On the basis of differential staining of chromosomes by Hiemse's dye 18 individuals (7,2%) were diagnosed to have insignificant changes in morphology of some chromosomes, considered as variants of caryotype. In the majority of cases these changes were of a family nature. On the medical examination mnay individuals were diagnosed to have different pathological features, though we did not succeed in revealing any correlation between a certain microanomaly of chromosomes and a pathological feature.

[Irradiation sensitivity of cells heterozygote for ataxia telangiectasia]. / Chuvstvitel'nost' k oblucheniiu kletok geterozigot po ataksii-teleangiéktazii.

The frequency of chromosome aberrations after in vitro exposure to different radiation doses in lymphocyte cultures of heterozygotes according to ataxia-teleangiectasia (AT) was compared to that in control donors. A increased frequency of dicentrics and rings of heterozygotic cells according to AT was observed upon exposure to relatively low radiation doses (40 and 80 rad). Meanwhile the increased dose (160 rad) brought about no differences. No differences were found in the frequency of cells with chromosome aberrations.

[Effect of thiophosphamide on the frequency of chromosome aberrations in cells heterozygous for ataxia-telangiectasia]. / Vliianie tiofosfamida na chastotu khromosonnykh aberratsii v kletkakh geterozigot po ataksii-teleangiéktazii.

Chromosome aberration rate in ataxia-teleangiectasia (AT) heterozygotes exposed to thiophosphamide in lymphocyte culture was compared to that in control donors. AT heterozygotes demonstrated an increased number of chromosome aberrations. The patterns of concentraion relationships in AT heterozygotes are depictable by the same equation as in control donors. However, the expected chromosome aberration rate in AT heterozygotes proved to be elevated, indicating the increased sensitivity of AT heterozygotes to the exposure to low doses of thiophosphamide, since no experimental differences were found in the spontaneous chromosome aberration rate between AT heterozygotes and control donors.