Biomedical subjects

S G Vorsanova

Publications and source records attributed to S G Vorsanova.

60 records · Page 4Linked to original sources

PubMedDate not supplied

[Unusual case of 18p- syndrome: diagnosis using a cloned DNA fragment].

The patient with atypical clinic picture of 18p- syndrome is described. The in situ hybridization technique was used to localize chromosome 18-specific cloned sequence to metaphase chromosomes of the proband. The predominant hybridization was found in pericentromeric regions of homologous chromosome 18. The amount of pericentromeric DNA measured by in situ hybridization was different in homologous chromosomes and the number of radioactive grains was statistically greater in the normal chromosome 18 than in the chromosome 18p-. The cause of asymmetrical hybridization of probes to homologous chromosomes 18 is discussed. The results obtained indicate that this probe may be useful in clinical cytogenetics for identification of chromosome 19 in metaphase and interphase cells, determination of breakpoints or studies of pericentromeric DNA polymorphisms.

Chromosome Deletion↗

PubMedDate not supplied

[A review of the data from cytogenetic and molecular cytogenetic research on human supernumerary minichromosomes].

The literature about the nature of marker chromosomes (mini-chromosomes of unknown origin) in patients with mental retardation, hereditary defects of development as well as in healthy individuals is reviewed. The advantage of the use of modern molecular methods of research for the analysis of nature and origin of additional mini-chromosomes is demonstrated.

Abnormalities, Multiple↗

PubMedDate not supplied

Identification of marker chromosomes by in situ hybridization technique using alpha and "classical" satellite DNA probes with relative chromosomal specificity.

Nine additional marker chromosomes in children with mental retardation and congenital malformation were investigated by routine cytogenetic and in situ hybridization techniques. Five metacentric non-satellited markers and four satellited markers of unknown origin were determined by routine and banding staining. To determine the origin of small marker chromosomes a special scheme involving the sequential application of definite alphoid and "classical" satellite DNA probes with the relative chromosome specificity was employed. The probes specific to four groups of definite chromosomes (i) 1, 3, 5, 6, 7, 10, 12, 16, 19; (ii) 2, 4, 8, 9, 13, 14, 15, 18, 20, 21, 22; (iii) 1, 11, 17, X; (iiii) 9, 13, 14, 15, 21, 22, Y and in situ hybridization under low stringency conditions were used at the first stage of experiments. After the preliminary analysis and the determination of possible origin of a marker chromosome from a definite group of chromosomes the probes with a strong chromosome-specificity under high stringency conditions were used. The approach involving the application of the original collection of chromosome-specific DNA probes, including molecular markers to practically all human chromosomes [1, 2], and various conditions of hybridization provides an effective method for detecting unknown markers. Marker chromosomes investigated in this study were derivatives of chromosomes 7, 9 (two cases), 13, 14, 21 (two cases), X and Y.

Chromosome Banding↗

PubMedDate not supplied

[Chromosomal anomalies in children with undifferentiated forms of metal retardation based on molecular cytogenetic research data].

The results of cytogenetic diagnosis of 1333 children with mental retardation and congenital malformations are presented. Chromosomal aberrations and chromosomal variants (1qh+, 9qh+, 16qh+) have been detected in 181 (13.9%) cases analyzed and in 158 (11.85%) cases, respectively. Molecular cytogenetic methods have been used for diagnosis or detalization of diagnosis in 42 cases from 181 (23.2%). Independent variation (or polymorphism) of copies number of "classical" and alpha-satellite DNA sequences, forming pericentromeric regions (1qh+, 9qh+, 16qh+) has been detected in patients with chromosomal variants.

Child↗

PubMedDate not supplied

[An analysis of human marker chromosomes originating from chromosome 21 by using in situ hybridization].

Four cases of patients with additional marker chromosomes are described. The clinical, cytogenetic and molecular cytogenetic methods have been used for investigation. The identification of marker chromosomes was made by using in situ hybridization and the collection of chromosome-specific DNA probes. All marker chromosomes were determined as originated from chromosome 21 with break-points in the region between 21q11 and 21q22.

Chromosome Aberrations↗

PubMedDate not supplied

Double color in situ hybridization of alpha-satellite chromosome 13, 21 specific cosmid clones for a rapid screening of their specificity.

Double color in situ hybridization was used to determine the specificity of cloned alpha-satellite cosmid DNA sequences belonging to satellite DNA sequences shared by chromosomes 13 and 21. It was determined that cosmid clone cos56D8 is more specific to chromosome 13, cosmid clone cos37E is more specific to chromosome 21 and cosmid clones cosA5130 is specific to both chromosomes 13 and 21. These new cosmid probes could bw useful in the molecular-cytogenetic analysis of trisomic cells at Patau or Down syndromes as well as in analysis of marker chromosomes originated from the chromosomes 13 and 21.

Cells, Cultured↗