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At least 19 recordsLinked to original sources
PubMed1975

Relative position of trypsin banded homologous chromosomes in human (female) metaphase figures.

"Generalized distances" between centromeres were statistically analyzed (chi2 test) on 50 normal female trypsin-banded metaphase figures. This study revealed that the homologous chromosomes of the pairs 13, 17, 14, and 21 lie closer together than would be expected by a reference distribution, and this in a statistically significant way. The same relative position was demonstrated for the chromosome groups 13-14, 13-21, 14-21, 15-22, and 14-22. Evidences were collected that also showed that homologous chromosomes of the pairs 1, 19, and 20 and the chromosome groups 15-21, 13-15, and 18-20 tend to lie closer together. Giving a functional interpretation to the phenomenon of non-random distribution of chromosomes in metaphase figures, it may be suggested that the chromosomes 13, 14, and 21 are involved in the organization of the human nucleolar organizers, more frequently than the other D- and G-group chromosomes.

Cell Nucleus↗
PubMed1976

Banding of human chromosomes with basic fuchsin.

In this paper a technique is described for the banding of human metaphase chromosomes with basic fuchsin. The main characteristics of the G-banding pattern obtained with this cationic triphenylmethane dye are: the secondary constriction regions of chromosomes Nos. 1 and 16 are strongly stained, especially in the latter one; the heterochromatic area of chromosome No. 9, usually negative with most other G-banding techniques, is clearly visible as an intensely stained band adjacent to the centromere; the chromosomal outline is often very distinct, facilitating the study of the telomeres; a number of chromosomal regions with bright Q fluorescence such as the polymorphic regions of the chromosomes Nos. 3, 4, and Y also stain strongly with basic fuchsin. The basic fuchsin technique combines therefore properties of G-, C-, and Q-banding methods and seems very suitable for use in e.g., family and linkage studies. Several triphenylmethanes closely related to basic fuchsin produce similar banding patterns. The band-producing ability is, however, diminished in those dyes which contain methylated amino groups. If the methyl groups are attached to the carbon atoms at the 3-positions in the phenyl rings, band formation seems unaffected. The way in which basic fuchsin and chromatin may interact as well as the possible mechanism(s) of band formation with this dye are discussed.

Chromosomes↗
PubMed1976

Negative silver staining in A-T and satellite DNA-rich regions of human chromosomes.

Human metaphase chromosomes were stained with silver following a pretreatment with a heated alkaline solution. The most conspicuous feature of the stained metaphases was the omission of silver staining in the secondary constrictions of chromosomes 1,9 and 16, and on the distal Yq. Our evidence indicates that the negative silver binding is due to the preferential removal or alteration of non-histone proteins associated with these regions. The cytochemical significance of these findings is discussed.

Adenine Nucleotides↗
PubMed1976

Method for the determination of mean densitometric profiles of chromosomes: application to human chromosomes stained by quinacrine mustard, ethidium bromide or by the Feulgen reaction.

When comparing the densitometric profiles of corresponding chromosomes registered from different metaphases or homologous pairs, one is always faced with the variability of their length and overall height. This makes difficult the quantitative comparison of a given chromosome treated by various staining procedures.--A simple and rapid method has been developed for normalizing the densitometric profiles and averaging them in order to obtain a "mean density pattern" of each chromosome. The analysis involves: photographic images, digitalization of the densitometric profiles and processing of the data by a mini-computer.--The method, based on a linear relationship between the area of the densitometric profiles and their length, has been applied to five human chromosomes (1, 2, 6, 12 and 16) stained by ethidium bromide, quinacrine mustard (with or without acidic hydrolysis), pararosaniline and bisaminophenyl-oxadiazole (Feulgen reaction).

Bromides↗
PubMed1976

Identification with G and R banding of the position of breakage points induced in human chromosomes by in vitro x-irradiation.

The aberrations seen in chromosomes of human peripheral-blood lymphocytes, X-irradiated in vitro, have been analysed in three types of preparations, treated to give G-banding; R-banding; and G-banding followed by R-banding on the same cells. The data from cells subjected to both banding techniques reveals that 30 per cent of the sites of chromosome breakage are situated at he interfaces between dark- and - light-stained bands. The results of all the analyses show that approximately 30 per cent of all breaks were located in either the telomere (19-5 per cent) or centromere (11-3 per cent) regions. Chromosomes rich in R-band material were not preferentially damaged, but chromosomes 12, 15, and particularly 17, were involved in aberrations more frequently than would be expected on the basis of their length. No breaks were found on the Y chromosome in the 114 male cells analysed, but the X did not appear to be spared from damage either in the male cells analysed, but the X did not appear to be spared from damage either in the male cell or the 136 female cells analysed. G and/or R-banding enables a much more accurate analysis of aberrations than can be obtained from the use of conventional staining techniques, and with these methods, it is shown that the numbers of induced asymmetrical and symmetrical exchanges are similar.

Chromosome Aberrations↗
PubMed1976

Inclusion of satellites in an 18/21 translocation chromosome shown by ammonical-silver staining (sat-banding) in case of partial trisomy 18.

A male infant with a partial trisomy 18 and a 46,XY, --21, t(18;21)(18qter replaced by 18q12::21 p13 replaced by 21 qter) chromosome complement is described. The translocation chromosome is of special interest because it includes the satellites of chromosome 21. This was shown by differential satellite staining with the ammoniacal-silver technique.

Ammonia↗
PubMed1975

Partial trisomy 10q occurring in a family with a reciprocal translocation t(10;18)(q25;q23).

Partial trisomy 10q was observed in an eighteen year old girl with severe mental and physical retardation, microcephaly, a high forehead, microphthalmia, antimongoloid slants, low set ears and severely malformed extremities. A balanced translocation t(10q-;18q+), present in several family members, was identified by fluorescence and thermic denaturation techniques; the break points were 10q25 and 18q23. A comparison made with seven similar cases suggests a common, phenotypical appearance which may be of diagnostic value.

Abnormalities, Multiple↗
PubMed1976

[The chromosome bands. Significance for clinical and cytogenetic research (author's transl)].

The methods of performing chromosomal investigations have been fundamentally changed in the last few years through the discovery of differential staining methods. While only a rough classification of the chromosomes into single groups could be carried out earlier, it is now possible to identify every individual pair of chromosomes on the basis of a typical pattern of bands. By means of these banding techniques smaller chromosomal variations can be recognized which were overlooked earlier and which have led to the delineation of new chromosomal malformation syndromes. In the present work, the modern methods of chromosome analysis are reviewed. Examples from clinical diagnosis show the necessity of using these techniques.

Abnormalities, Multiple↗
PubMed1976

The segregation of C-band polymorphisms on chromosomes 1, 9, and 16.

Eleven normal families with at least four children were studied cytogenetically using the C-band technique to identify polymorphisms in the constitutive heterochromatin of chromosomes 1, 9 and 16. Thirteen individuals showed one or more variants in such chromosomes. The analysis of the segregation ratios in the 35 offspring of these 13 individuals showed that these marker chromosomes generally segregated according to the expected 50:50. However, one of these variants, chromosome no. 9 with an increased heterochromatin block in the secondary constriction, has an apparently preferential segregation, when the findings from this study are combined with those of other authors.

Chromosomes, Human, 1-3↗
PubMed1978

The pure gonadal dysgenesis syndrome.

Two cases of gonadal dysgenesis in phenotypic females associated with different chromosomal patterns are discussed. Both patients presented with primary amenorrhea and were characterized by tall stature and underdeveloped secondary sex characteristics and external and internal reproductive organs. The karyotype of the first patient was 46,XX with a satellite on chromosome 17. The second patient had a normal female chromosome composition (46,XX) with a past history of mumps. Laparoscopic bilateral gonadal biopsies in both patients revealed fibrous tissue without any primordial follicles. This report emphasizes the pathogenesis, clinical significance, diagnosis and management of gonadal dysgenesis.

Adolescent↗
PubMed1976

Prenatal diagnosis of congenital anomalies in an intrauterine growth retarded fetus.

Chromosome analysis of amniotic fluid cells and amniotic fluid alpha-fetoprotein determinations were used to investigate a fetus with severe intrauterine growth retardation in the third trimester. The karyotype was 47,XY,18+ and increased alpha-fetoprotein levels indicated the presence of congenital malformations. We suggest that when severe fetal growth retardation is detected early in the antepartum course, amniotic fluid alpha-fetoprotein and amniotic fluid cell chromosome studies be done to determine if congenital anomalies may be an etiological factor.

Abnormalities, Multiple↗