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H A Lubs

Publications and source records attributed to H A Lubs.

At least 19 recordsLinked to original sources
PubMed1978

Size and pericentric inversion heteromorphisms of secondary constriction regions (h) of chromosomes 1, 9, and 16 as detected by CBG technique in Caucasians: classification, frequencies, and incidence.

Eighty normal Caucasians were studied by CBG technique for estimation of size and inversion heteromorphisms of chromosomes 1, 9, and 16. Size heteromorphisms were classified into one of five sizes using 16p as a reference standard: very small, small, intermediate, large, and very large. Inversion heteromorphisms were also classified into 5 categories - eg, no inversion; partial inversion - minor; half inversion; partial inversion - major; and complete inversion. The frequencies of size heteromorphisms for chromosomes 1, 9, and 16 were 11.3%, 47.5%, and 7.5%, respectively. Thirty-four chromosomes were found to have inversions. Of these, 16 were in chromosome 1, and 18 were in chromosome 9. No inversions were found in chromosome 16. An increase in the size of the h region was more frequently associated with inversion, suggesting that there is a possible relationship between size and inversion. For example, there were 118 chromosomes that were classified as "intermediate" by size; 23 (19.5%) had inversions. In contrast, there were 225 that were "small" in size, and only 10 (4.4%) had inversions. There was no significant difference between males and females for size and position heteromorphisms.

Adult↗
PubMed1978

Length heteromorphisms of fluorescent (f) and non-fluorescent (nf) segments of human Y chromosome: classification, frequencies, and incidence in normal Caucasians.

Sixty normal male Caucasians were selected to study the length of the Y chromosome. QFQ banding was performed. Chromosomes 19 and 20 (F) and Y were measured directly from the film. Y/F, f/F, and nf/F indices (f = fluorescent; nf = non-fluorescent segment) were determined. The length of the Y chromosome was classified into 5 groups; very small, small, average, large, and very large with Y/F indices of less than 0.8, 0.81--0.94, 0.95--1.09, 1.1--1.23, and greater than 1.23, respectively. The frequencies of Y/F indices for these groups were 0 (0%), 9 (15.0%), 40 (66.7%), 8 (13.3%), and 3 (5.0%), respectively. The most frequent class was 0.95--1.09 and was defined as the 'average' Y/F index for the human Y chromosome. The variation in the total length of the Y chromosome was accounted for by variations in the length of the non-fluorescent as well as the fluorescent segments. No relation between f and nf segments was observed. The mean Y/F, f/F, and nf/F indices were 1.022, 0.441, and 0.574, respectively.

Adult↗
PubMed1978

Linkage and gene localization of hereditary spherocytosis (HS).

Fifteen kindreds with dominant hereditary spherocytosis (HS) were studied. Expansion of the data from a family with an 8/12 translocation provided further evidence that at least one locus for HS is located near the breakpoint of the translocation. Linkage analysis of all families showed a lack of linkage with all marker loci studied except for Gm (IgG). Linkage between Gm and HS was shown to be significant with a maximum lod score of 3.42 at a recombination fraction of 22%. No heterogeneity of the recombination fraction was observed either between sexes or between families. These results are compatible with the hypothesis that HS is not a heterogeneous disorder.

Female↗
PubMed1977

Size variation polymorphisms of the short arm of human acrocentric chrosomes determined by R-banding by fluorescence using acridine orange (RFA).

One hundred normal Caucasians were studied by the RFA technique to estimate the frequencies of size variation of the short arm of acrocentric chromosomes. Each size variation was classified into one of five levels. The most frequent size level(code) was 3; therefore, this was regarded as the 'average' size. If one excludes the average size, the frequencies of size variation by RFA for chromosome 13, 14, 15, 21, and 22 were 22.5, 19.5, 14.5, 19, and 17% respectively. There was no significant difference for the overall frequencies of size variation between sexes. Furthermore, the RFA technique detects more variation in the size of human acrocentric chromosomes than any other method.

Acridines↗
PubMed1977

Classification of qh regions in human chromosomes 1, 9, and 16 by C-banding.

We present a classification for secondary constriction (qh) regions with C-banding technique in chromosomes 1, 9, and 16 by means of comparing them to the short arm of chromosome 16. It is simple and convenient and can be used routinely. It can be incorporated into the modified Paris nomenclature system.

Chromosomes, Human↗
PubMed1977

A possible association of long Y chromosomes and fetal loss.

Long Y chromosomes is a relatively unbiased large sample of newborn infants were measured. The proportion of prior abortions was increased twofold in mothers of long Y infants compared to the control in the Caucasian sample. Our results indicate that an increased length of Y chromosome may be an important cause of fetal loss.

Abortion, Habitual↗
PubMed1977

Two cases of Down syndrome with unusual de novo translocation.

Two children with the clinical features of Down syndrome were found to have several unusual cell lines. In both cases the same reverse tandem translocation between two 21 chromosomes was present in one line. This may be an unstable rearrangement. In addition, the findings offer some support for current efforts to localize the portion of chromosome 21 responsible for clinical features of Down syndrome to band 21q22. Acridine orange R banding was found to be especially useful in the identification of the break points on the translocations. The origin of the abnormality was found to be paternal in one case and was indeterminate in the second.

Cell Line↗
PubMed1977

Frequency of RFA colour polymorphisms of human acrocentric chromosomes in caucasians: interrelationship with QFQ polymorphisms.

One hundred normal caucasians were studied by sequential QFQ and RFA in order to estimate the type and frequency of variation. Colour variants were classified into 1 of 6 colours by RFA and intensity variations into 1 of 5 levels by QFQ. The interrelationship between QFQ and RFA variants was also examined. It was found that there was no consistent relationship between negative or brilliant QFQ variants and the various colours observed with RFA. RFA colour polymorphisms for chromosomes 13, 14, 15, 21 and 22 were 33.0, 38.0, 28.0, 50.0 and 24.5% while QFQ frequencies were 56.5, 10.0, 10.0, 15.5 and 10.0% respectively. RFA is especially useful in studying the inheritance of chromosome 21.

Adult↗
PubMed1976

Description of the banding patterns of human chromosomes by acriding orange reverse banding (RFA) and comparison with the Paris banding diagram.

A reference diagram is presented which is comparable to the Paris banding diagram but which was based primarily on chromosomes studied by acridine orange reverse banding. Comparison with the Paris Conference (1971) banding diagram was made. Bands were combined in 13 instances and subdivided in 10 cases. The number of bands was found to depend primarily upon the length and quality of the chromosomes. No major differences between the present diagram and the Paris banding diagram were observed. Moreover, the results with acriding orange reverse banding were comparable to those previously reported with Giemsa R banding. In addition, sequential Q banding and R banding were carried out in the same cells. No significant differences in resolution of bands were observed when these two techniques were compared.

Acridines↗
PubMed1976

Additional observations on the preparation of R banded human chromosomes with acridine orange.

A number of technical factors which affect acridine orange R banding (RFA banding) were studied. These variables included age of slide, timing of fixation, details of incubation mounting and the use of sequential technics. Optimal RFA banding was obtained between 15 and 20 days but good or very good preparations were obtained between 7 days and 2 months. Improved results were obtained in slides that were 3-4 months old by refixing the slides in ethanol acetic acid. Intermittent movement of slides during incubation in buffer as well as the details of mounting and removal of cover slips were found to be important. The best sequential banding was obtained with the sequence of Q to R but good results were obtained with the sequence G to R using ASG banding. Satisfactory results with the sequence R to C were not obtained. With careful attention to these variables good RFA binding can be obtained over a period of several months.

Acridines↗
PubMed1976

Comparison of G-, Q-, and R-banding in 28 cases of chromosomal abnormalities.

Twenty-eight cases of chromosomal abnormalities were ascertained using G-banding. Seventeen of these had structural abnormalities of a complex nature and are discussed in detail. An independent assessment of chromosome abnormalities was carried out using sequential Q- and R-banding. In no case was there a difference in the identification of the abnormal chromosome, but in two cases a more precise localization or definition of the abnormality was obtained from the R-banded cells. In one case the initial diagnosis of the terminal deletion was altered to interstitial deletion; in the second case a break point in one chromosome involved in a reciprocal translocation was found to be in a different band by R-banding. In several others better delineation of break points or confirmation of complex abnormalities was obtained from the R-banded cells. R-banding was especially helpful in the localization of break points because of the color differentiation obtained with acridine orange. Q-banding was not found to have added any additional information. It was concluded from this study that the use of both G-banding and R-banding in complex abnormalities proved worthwhile.

Chromosome Aberrations↗