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A Mayerová

Publications and source records attributed to A Mayerová.

At least 19 recordsLinked to original sources
PubMed1993

Inverted and satellited Y chromosome in the orangutan (Pongo pygmaeus).

An inverted and satellited Y chromosome of almost acrocentric appearance was detected in seven of 14 male orangutans. In the remaining seven animals a submetacentric Y chromosome without NORs occurred. The high frequency with which the satellited Y chromosomes were associated with acrocentric autosomes and the positive AgNO3-staining of their satellite stalks clearly indicate the active state of the NOR on the Y chromosomes. DNA fingerprinting in two orangutan families showed that the inverted and satellited Y chromosomes in carrier orangutan males do not interfere with normal fertility. Within our sample of male orangutans studied, the inverted and satellited Y chromosome is restricted to Sumatran animals; all Bornean specimens possessed the submetacentric Y chromosome. The question arises whether these two kinds of Y chromosome differ constitutively between the Pongo pygmaeus subpopulations.

Animals↗
PubMed1992

Clinical reinvestigation and linkage analysis in the family with Episkopi blindness (Norrie disease).

We present the results of a clinical and genetic reinvestigation of the Cypriot family affected by an X chromosomally inherited eye disease originally published by Taylor et al, who coined the term Episkopi blindness. The pedigree was extended to 160 members, including 16 affected males out of 48 males at risk for the disease, most of whom were seen by one of us (PA). Affected males are blind with no associated symptoms and apparently are not mentally retarded. Thirty-nine family members agreed to blood sampling for genetic investigations. RFLP analysis was performed using probes from the region known to be deleted in some Norrie patients and polymorphic markers (DXS77, DXS7, MAOA, DXS255) from the proximal short arm of the X chromosome. There was no deletion for any of the probes in the affected males. Linkage analysis yielded positive lod scores for all informative markers (Z (DXS255, theta = 0) = 6.54, Z (MAOA, theta = 0) = 2.23, Z (DXS7, theta = 0) = 2.13). Thus, the conclusion that Episkopi blindness and Norrie disease (NDP, MIM *310600) are the same entity based on clinical evidence is now reinforced by gene mapping.

Adult↗
PubMed1992

[Prenatal virus infections and orofacial clefts].

A potential teratogenic activity of virus infections caused by the viruses of rubella, influenza, parotitis, hepatitis B, cytomegalovirus and the Epstein-Barr virus was investigated. Specific antibodies against these viruses were examined serologically in children with orofacial clefts and in their mothers and the results were compared with those obtained in control children and their mothers. Different micromethods were used in performing the examinations (ELISA, RIA, NIR, KFR, HIT). Evaluation of the results and their statistical processing supports the assumption that prenatal infection may have occurred in the series studied induced by the viruses of influenza, rubella, cytomegalovirus, and possibly also by the Epstein-Barr virus. No association with the viruses of parotitis and hepatitis B was established. (Tab. 5, Ref. 36.)

Antibodies, Viral↗
PubMed1991

[Genetic counseling in prenatal diagnosis of cystic fibrosis].

In this paper we discuss the possible results of post- and prenatal DNA-diagnosis in cystic fibrosis with respect to the modification of the risk of having an affected child, depending on how closely the affected patient is related to those seeking advice. For parents with an affected child post- and prenatal DNA-diagnosis yields very reliable results and is an important factor in their decision process. In contrast to this, DNA-diagnosis for other relatives or individuals without an affected family member can lead to results which may intensify conflicts of decision making. This stresses the growing importance of genetic counseling before and after genetic diagnostic measures for cystic fibrosis.

Chorionic Villi Sampling↗
PubMed1988

Serological H-Y antigen in the female chicken occurs during gonadal differentiation.

In the chicken, serological H-Y antigen is specific for the female sex. Male gonad differentiation can be experimentally influenced by estrogens, resulting in the transient formation of an ovotestis. The sex-inverted gonad becomes positive for H-Y antigen. Therefore, the question arises whether, in normal gonadogenesis also, the female gonad at the indifferent stage, before estrogens are produced, is negative for H-Y antigen. Here we show that this is indeed the case. The female gonad becomes positive for H-Y antigen when the ovary starts its organotypic differentiation at about day 6 1/2 of embryonal development. It is assumed that estrogens are responsible for the occurrence of H-Y antigen. This finding supports the view that H-Y antigen plays a role in primary ovogenesis in the chicken.

Animals↗
PubMed1987

Coagulation factor XIII: genetic linkage studies with F13B.

Linkage relations of the F13B gene with 38 marker genes are analyzed, which, along with the data of earlier reports on the same subject, brings the number of comparisons to a total of 49. Practically all the lod scores are totally negative. This will mean that the F13B gene can hardly be located on the chromosomes/chromosome arms 1p, 2p, 4q, 6p, 14p, 15p, 20q, 21p, 22 and also not on longer segments of 3q, 6q, 7q, 9p, 9q, 11q, 13q, 14q, 16p, and 16q.

Child↗
PubMed1987

Absence of Y-specific DNA sequences in human 46,XX true hermaphrodites and in 45,X mixed gonadal dysgenesis.

A search for Y-specific DNA sequences has been performed in a sample of seven 46,XX true hermaphrodites and one 45,X mixed gonadal dysgenesis case and compared with a sample of 11 XX males. Using six Y-specific DNA probes no hybridization signal was obtained in the hermaphrodite group; in contrast, all XX males gave a positive signal with at least one probe. This difference is statistically highly significant. We conclude that the aetiology of true hermaphroditism is different from that of the XX male syndrome. As all cases of the hermaphrodite group are positive for the serological sex-specific antigen (Sxs) it is concluded that this antigen can be present even in the absence of Y-specific DNA.

DNA↗
PubMed1987

The occurrence of serological H-Y antigen (Sxs antigen) in the diandric protogynous wrasse, Coris julis (L.) (Labridae, Teleostei).

The serological sex-specific (Sxs) antigen (previously called 'H-Y antigen') has been shown, in various vertebrate species ranging from fish to mammals, to be characteristic of the heterogametic sex. We studied a protogynous hermaphrodite, Coris julis, in order to examine whether the change of a female to a secondary male also involves a change in the Sxs-antigen phenotype. The (homogametic) females of this species were found to be Sxs negative, while both primary and secondary males were Sxs positive. This was true not only for gonads but also for nongonadal tissues. The administration of androgen to females is known to cause sex inversion in this species; we were able to demonstrate this again at the histological level, and found that androgen results in a Sxs positive phenotype in all tissues studied (gonads, spleen, muscle). We propose that androgen is responsible, directly or indirectly, for the occurrence of the Sxs antigen.

Animals↗
PubMed1987

Linkage studies in a pedigree with Van der Woude syndrome.

A kindred segregating for Van der Woude syndrome (VWS) through five generations is described. Biochemical and serological phenotypes at 36 polymorphic marker loci have been determined, of which 27 were informative for linkage analysis to the VWS gene (LIPED 3 computer programme). Lod scores are reported and show exclusion of close linkage for most of the marker loci. Only VWS:Duffy (Fy) resulted in uniformly positive lod scores (theta = 0.0, z(theta) = 1.31).

Cleft Lip↗
PubMed1985

Serologically H-Y antigen-negative XO mice.

In a series of six independent experiments organ homogenates of 35 mice of the XX, XO or XY sex chromosome constitutions were absorbed using three different anti-H-Y antisera raised in inbred female LEW rats. Residual activities of absorbed antisera were tested in the Raji cell, complement-dependent, cytotoxicity test. Homogenates of various tissues, including the gonads, of XX and XO females were equally unable to absorb H-Y antibodies, indicating that tissues of these mice do not carry the H-Y antigen. In contrast, XY male homogenates fully absorbed H-Y antibodies of antisera at concentrations of 1/2 to 1/4. We discuss our findings with special attention to the problem of the existence of one or more H-Y antigens and, to the genetic regulation of the expression of this antigen.

Animals↗
PubMed1984

Virilization without adrenal hyperplasia in 21-hydroxylase deficiency during fetal life.

The characteristic excess production of androgens in the cortisol 21-hydroxylase defect is generally considered to be secondary to ACTH stimulation of alternate pathways. Whenever a morphological examination of the adrenals has been possible in this disorder, adrenocortical hyperplasia was a constant finding. The availability of methods for the prenatal diagnosis of the 21-hydroxylase defect has made it possible to examine some of the manifestations of this disorder during fetal life. We studied a severely virilized 20-week-old aborted female fetus with the 21-hydroxylase defect whose adrenals were neither grossly enlarged nor microscopically hyperplastic. In a pregnancy at risk for congenital adrenal hyperplasia due to a 21-hydroxylase deficiency, amniocentesis was performed in the 18th week of gestation. The 21-hydroxylase defect was established by HLA typing and highly elevated levels of 17-hydroxyprogesterone, testosterone, and androstendione in amniotic fluid. After counselling, the parents, who already had a girl with the salt-wasting form of 21-hydroxylase deficiency, wished termination of the pregnancy. The aborted 20-week-old fetus was within the normal range for gestational age in weight and height. The external genitalia were ambiguous and extremely virilized, with an enlarged clitoris and fused labioscrotal folds. A urogenital sinus opened at the base of the clitoris. The internal organs were female, with a normal uterus and ovaries. Both adrenals were normal in size and weight for their gestational age. Histological examination of the adrenals revealed no abnormalities, and no hyperplasia was detectable. Thus, the adrenals in the 21-hydroxylase defect during fetal life secrete excessive amounts of androgens and cause virilization in the absence of adrenocortical hyperplasia.

Adrenal Hyperplasia, Congenital↗
PubMed1983

Genetic linkage relations of the human plasminogen gene.

No evidence for close linkage was found between the human plasminogen (PLGN) locus and 35 other marker genes using the LIPED 3 computer program of Ott (1974). Although positive lod scores were found for PLGN-GC relations in females, the lack of linkage between the two loci in males demands that the reported assignment of the PLGN locus to chromosome 4 (Eiberg et al. 1981) should be considered with reservations.

Female↗
PubMed1983

C6 linkage studies.

Explore the source record for details and available documents.

Chromosome Mapping↗
PubMed1983

The X linked recessive form of XY gonadal dysgenesis with a high incidence of gonadal germ cell tumours: clinical and genetic studies.

Five phenotypic females in one family had the genotype 46,XY and all had gonadal germ cell tumours. Studies of the family pedigree suggest that this form of XY gonadal dysgenesis is inherited in an X linked recessive manner. G banding of elongated metaphase chromosomes from two subjects with XY gonadal dysgenesis and a female carrier showed no aberrations of the X chromosome. The titres of H-Y antigen in three girls with XY gonadal dysgenesis were in the male control range. Thus it appears that, in the X linked form, XY gonadal dysgenesis may be caused by a point deletion or mutation of a gene on the X chromosome, which controls the gonad specific receptor for the H-Y antigen. Studies of Xg blood groups were uninformative about linkage of Xg with the X borne gene causing the XY gonadal dysgenesis. Dermatoglyphic studies in the girls with XY gonadal dysgenesis and female carriers revealed high a-b palmar ridge counts and a tendency for the A mainline to terminate in the thenar area. Both of these features have been described in patients with Turner's syndrome.

Adolescent↗
PubMed1982

Correlation between the number of sex chromosomes and the H-Y antigen titer.

H-Y antigen was studied serologically on blood cells and cultured fibroblasts of patients with numerical aberrations of the sex chromosomes. As compared with normal males, patients with the karyotypes 48,XXXY and 49,XXXXY have reduced H-Y antigen titers; a tendency toward reduced titers can also be detected in the 47,XXY Klinefelter syndrome. The existence of an intermediary titer was further substantiated by a quantitative absorption test applied to cells with the 49,XXXXY karyotype. It appears that in the presence of one Y chromosome, the H-Y antigen titer decreases with an increasing number of X chromosomes. In contrast, the H-Y antigen titer is increased if, at a given number of X chromosomes, the number of Y chromosomes is increased, as in the 47,XYY male. Consequently, patients with 48,XXYY chromosomes are in the male control range. The findings are interpreted under the hypothesis of a controlling or modifying influence of the sex chromosomes on the titer of H-Y antigen.

Adolescent↗