[Molecular genetic aspects of neoplasms]. / Molekuliarno-geneticheskie aspekty zlokachestvennykh novoobrazovanii.

The paper presents data on the role of some genes that provide normal positive and negative regulation of cell proliferation. It considers their structural and functional changes that lead to the occurrence and progression of tumors. The characteristics of tumor suppressive genes whose inactivation determines hereditary predisposition to some forms of malignant neoplasms.

[Characterization of cloned alpha-satellite sequence from the extrachromosomal DNA of HeLa cell culture]. / Kharakteristika klonirovannykh al'fa-satellitnykh posledovatel'nostei iz ékstrakhromosomnykh DNK kul'tur kletok HeLa.

We have obtained the alphoid DNA clones, pK1 and pK2, from the extrachromosomal DNA of Hela cells treated by cycloheximide (30 micrograms/ml). Nucleotide sequences of the clones were aligned. The sides of the pK1 and pK2 are 390 and 184 bp, respectively. The marked RELP for the clones was not observed. The results of in situ hybridization have shown an approximately equal distribution of Ag-grains over major part of human chromosomes, with a slight preference for chromosomes 1, 5 and 19 (the 1-st group of alpha-satellite DNA). Therefore, the obtained alphoid sequences seem to be rather conservative and non-chromosome-specific. We suppose that increase of the alphoid DNA content in the fraction of the extrachromosomal DNA under the cycloheximide treatment is a result of the sporadic statistical processes rather then consequence of the specific excision.

[Increase in the quantity of highly repetitive sequences in extrachromosomal circular DNAs under inhibition of translation by cycloheximide]. / Uvelichenie soderzhaniia vysokopovtoriaiushchikhsia posledovatel'nostei v ékstrakhromosomnykh kol'tsevykh DNK pri tormozhenii transliatsii tsiklogeksimidom.

Small polydispersed circular DNA(spcDNA) was isolated from cultivated HeLa cells. Cells were treated by cycloheximide in concentrations of 1 and 50 micrograms/ml. Gradient fractions were dot blotted to nitrocellulose filters and were hybridized with different repetitive DNAs. The pool of repetitive DNA sequences in fraction of spcDNA increased for cycloheximide treated cells. The content of Alu sequences increased by 1.5-2.5 times, "classical" satellite DNA--by 5-7 times, alpha-satellite--by 3-5 times.

[Analysis of the association of inherited predisposition to breast cancer with c-Ha-ras-1 oncogene alleles]. / Analiz assotsiatsii nasledstvennoi predraspolozhennosti k raku molochnoi zhelezy s allel'nymi variantami c-Ha-ras-1 onkogena.

Polymorphism of the human c-Ha-ras-1 gene has been analysed in 66 BamHI restricted DNAs from blood of 35 patients with "inherited" breast cancer, 7 fibroadenoma patients, 13 healthy first-degree relatives and 11 unaffected controls. Two "common" and four "unusual" alleles were detected. The frequency of "common" (6.6 and 7.4 kb) and "unusual" (6.9 kb) alleles was identical to that in the control and unaffected groups (65.8, 17.1 and 7.1%). Rare alleles (7.6 and 7.8 kb) were only detected in breast cancer patients and in healthy first-degree relatives. A 8.0 kb allele specific for control patients was also detected. No absolute relationship between the genetic predisposition to breast cancer and the Ha-ras genotype was assumed.

[Specificity of the location of human chromosomes in the nucleus of a moving cell]. / Spetsifichnost' raspolozheniia khromosom cheloveka v iadre dvizhushcheisia kletki.

Data are presented on the distribution of centromeric heterochromatin of the human X-chromosome in the interphase nucleus of a moving cell. The in situ hybridization made it possible to obtain some results leading to the following conclusions: in moving fibroblasts centromeric heterochromatin of the X-chromosome is located in end regions of the interphase nucleus; there was no preferential localization noted of the centromeric region of the X-chromosome in the front or back areas of the nucleus as to the direction of the movement.

[Isolation and molecular cytogenetic characteristics of the alpha-satellite DNA of human chromosome 6]. / Poluchenie i molekuliarno-tsitogeneticheskaia kharakteristika al'fa-satellitnoi DNK khromosomy 6 cheloveka.

In this work a molecular-cytogenetic characteristic has been given to the alpha-satellite DNA of chromosome 6. Using different restrictases made it possible to evaluate structural heterogeneity of the obtained subgroup of the alphoid DNA. Polymorphic restriction fragments of DNA have been found which can be used in determining linkage groups.

[Acquisition of the sequence of a new subclass of human alpha- satellite DNA, localized in the centromere regions of two pairs of acrocentric chromosomes]. / Poluchenie posledovatel'nosti novogo podklassa al'fa-satellitnoi DNK cheloveka, lokalizovannoi v tsentromernykh raionakh dvukh par akrotsentricheskikh khromosom.

The results are presented in the paper on obtaining of a clone of sub-group of alpha-satellite human DNA localized in heterochromatin regions of two pairs of acrocentric chromosomes. The obtained repeated DNA sequence is represented in a genome by some 20,000 copies. Using of the blot-hybridization method made it possible to show the polymorphic restriction variant distribution being preserved in different individuals genomes. Intergenomic structural heterogeneity in this alpha-satellite DNA sub-group has been found only by using restriction endonuclease BamHI.

[A new approach to cloning of tandem repetitive DNA sequences]. / Novyi podkhod k klonirovaniiu tandemno-organizovannykh povtoriaiushchikhsia posledovatel'nostei DNK.

A new approach to screening of the repeated human DNA sequences tandemly arranged in the genome is described. Efficiency of the developed approach for search of tandemly arranged DNA sequences is corroborated by the obtained experimental data.

[Relation between the intensity of transcription and the rRNA gene content of individual nucleolar-forming regions of human chromosomes]. / Zavisimost' mezhdu intensivnost'iu transkriptsii i soderzhaniem genov rRNK v individual'nykh iadryshkoobrazuiushchikh raionakh khromosom cheloveka.

A comparison has been carried out of satellite strand lengths, Ag-staining intensity and labelling intensity in in situ hybridization of 3H-thymidine-labelled 28S-rRNA gene fragment in nucleolar-forming regions (NFR's) of individual acrocentric chromosomes from blood lymphocytes of 2 karyotypically normal individuals. To identify chromosomes modified R-staining was performed (5-bromdesoxy-pyridine + Höchst fluorochrome 33258 + Giemsa dye). The data obtained demonstrate, firstly, the variability between 10 acrocentric human chromosomes both in the content of ribosome genes and in silvering intensity and NFR satellite strand length and, secondly, a positive correlation between three studied characteristics of individual chromosomes. In one case an exception has been noted in one homologue of chromosome 21 of an individual A: high intensity of hybridization labelling was accompanied by weak Ag-staining and short satellite strand. It was concluded that the variability of transcription activity of individual NFR's detected by Ag-staining is, as a rule, based on the variability in the content of ribosome gene DNA in them and, in some cases, the presence of rRNA gene copies in inactive state.

[Molecular and cytogenetic approach to the mapping of methylated polymorphic restriction fragments of human rRNA genes]. / Molekuliarno-tsitogeneticheskii podkhod k kartirovaniiu metilirovannykh polimorfnykh restriktsionnykh fragmentov genov rRNK

Combined restriction with Bam H I and Sal I (or Hpa II) has revealed Bam H I fragment on a non-transcribed spacer of rRNA genes in one out of four individuals under study. Using Ag-staining and hybridization in situ, chromosome 13p+ enriched by inactive rRNA gene copies was found in the given individual. Since Sal I does not restrict methylated sequences and rRNA genes are repressed by methylation, it is concluded that methylated Banm I-restricted rRNA gene fragments of non-transcribed spacer are localized in chromosome 13p+ of the individual in question.

[Characteristics of inheritance of restriction fragment polymorphisms for non-transcribed spacers of human rRNA genes]. / Zakonomernosti nasledovaniia polimorfnykh restriktsionnykh fragmentov netranskribiruemykh speiserov genov pRNK cheloveka.

Inheritance of polymorphous restricts of nontranscribed spacer (NTS) located to the right from 3'-end of 28S rRNA gene has been studied in families. Single classes of NTS polymorphous fragments are presented in the genome by some tenths of copies and are inherited as a simple mendelian characteristic located on separate chromosomes.

[Genetic analysis of the Ehlers-Danlos syndrome in a large family tree]. / Geneticheskii analiz sindroma Elersa-Danlosa v bol'shoi rodoslovnoi.

The results of genetic investigation of Ehlers - Danlos syndrome in the kindred of 205 members are presented. The autosomal dominant inheritance hypothesis was tested using two modes of ascertainment, complete and truncated. The data from the segregation analysis provide evidence for the Ehlers - Danlos syndrome type I being inherited as an autosomal dominant trait.