Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q00604 (X-linked)
 16,883 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the last fifteen years, therapeutic use of intravenous immunoglobulin on one hand, and of bone marrow transplantation on the other, have largely modified survival rate and prognosis for many primary immunodeficiency diseases. At the same time, major advances in molecular genetics have allowed mapping of several immunodeficiency genes and made prenatal diagnosis feasible. Furthermore, for many X-linked immunodeficiencies, carrier detection can be also accomplished by means of analysis of the pattern of X-chromosome inactivation. As a whole, these techniques have substantially contributed to a more accurate genetic counseling in the families.
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PMID:[Primary immunodeficiency 1991: new uses and prospects of genetic counseling]. 189 77

While inherited X-linked (XL) isolated thrombocytopenia is a mild condition, the Wiskott-Aldrich syndrome (WAS) associates severe thrombocytopenia with an immunodeficiency component and has a poor prognosis. Whether these conditions correspond to separate genetic entities or to different mutations of the same gene(s) remains unresolved. The Wiskott-Aldrich syndrome locus has been assigned to Xp 11.2 by means of RFLP studies. The X-inactivation pattern in female carriers has been found to follow a skewed pattern in the hematopoietic cells, thus allowing carrier detection. We studied a family with four members affected by XL thrombocytopenia and report the results of genetic segregation analysis, together with the X-inactivation pattern of hematopoietic cells from an obligate female carrier. Although the affected locus mapped to the same region as that of WAS, lymphocytes presented a skewed pattern of X-inactivation, whereas polymorphonuclear lymphocytes (PMN) did not. These results provide further evidence that the Wiskott-Aldrich syndrome and XL thrombocytopenia are different expressions of mutations within a single locus and that the severity of the disease corresponds to distinct hematopoietic cell selections in obligate carriers.
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PMID:X-linked thrombocytopenia and Wiskott-Aldrich syndrome: similar regional assignment but distinct X-inactivation pattern in carriers. 191 30

Between a third and half of all males with SCID and no family history of immunodeficiency represent the first manifestation in their family of a new mutation of the gene that causes X-linked SCID. These patients, like boys with a positive family history of X-linked SCID, have markedly reduced numbers of T cells, elevated numbers of B cells, and hypogammaglobulinemia. The hypogammaglobulinemia is due, at least in part, to the expression of the gene defect in B cells as well as in T cells. Patients with X-linked SCID who are treated with bone marrow transplant tend to engraft T cells readily but they do not engraft B cells unless they are treated with cytoreductive therapy prior to transplant. B-cell function after transplant tends to be poor, even in patients who have received transplants from HLA matched siblings. Better transplant strategies are required to achieve optimum long-term results in patients with X-linked SCID.
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PMID:X-linked severe combined immunodeficiency. 193 18

Common variable immunodeficiency is a heterogeneous syndrome which may occur at any age and may be associated with recurrent sinopulmonary and gastro-intestinal infections, atopic illness, autoimmune disorders and varying degrees of hypogammaglobulinaemia (1). The clinical syndrome is very similar to that described in X-linked agamma-globulinaemia but the mode of inheritance is unknown (2). In this communication, a patient with Turner's syndrome with X-isoX chromosomal pattern in conjunction with common variable immunodeficiency is reported.
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PMID:Common variable immunodeficiency in association with Turner's syndrome. 196 51

The gene for the Wiskott-Aldrich syndrome, an X-linked immunodeficiency disease, has been mapped between the RFLP markers DXS7 and DXS14 on the short arm of the X-chromosome. Close linkage to these markers permits accurate carrier detection and prenatal diagnosis. In one family with WAS patients in two generations, RFLP analysis was applied to three women at risk. It could be determined with more than 98.5% accuracy that these women were not carriers.
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PMID:[Genetic carrier detection for the Wiskott-Aldrich syndrome using restriction fragment length polymorphism analysis]. 197 11

Congenital thrombocytopenia may occur in isolation or accompanied by eczema and immunodeficiency, as part of the X-linked hereditary Wiskott-Aldrich syndrome (WAS). Because the clinical and immunologic picture of WAS is variable, particularly early in life, definite diagnosis cannot always be made in cases with a negative family history. Two unrelated males with sporadic congenital thrombocytopenia had only questionable immunologic abnormalities as infants, making them clinically indistinguishable from cases of isolated thrombocytopenia, although one developed episodic neutropenia and the other began to manifest a multisystem autoimmune disease at 2 years of age. Evaluation of X chromosome inactivation in the T cells of both patients' mothers showed each of these women to have the same highly skewed X chromosome inactivation pattern seen in carriers of typical familial WAS. A T-cell defect was subsequently directly demonstrated in the second patient, whose lymphocytes failed to proliferate to periodate and anti-CD43. Taken together, these data suggest the presence of T cell immunodeficiency consistent with WAS in these patients. Furthermore, their mothers were found to have a very high likelihood of being carriers, lending support to the diagnosis of a hereditary disease in these boys and making possible genetic prediction in other family members and subsequent pregnancies.
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PMID:Atypical presentation of Wiskott-Aldrich syndrome: diagnosis in two unrelated males based on studies of maternal T cell X chromosome inactivation. 199 98

X-linked immunodeficiency with hyperimmunoglobulinemia M (XHM) reflects an impairment of the immunoglobulin (Ig) heavy (H) chain class switch of B lymphocytes from IgM to IgG and IgA. XHM is recessive; female carriers manifest normal IgG and IgA production. Due to random X chromosome inactivation in all somatic cells of females, about half of the lymphocytes of XHM carriers are not able to express an intact XHM gene. An intrinsic defect of the Ig H chain class switch mechanism in XHM B lymphocytes would thus lead to a skewed X chromosome inactivation pattern in the IgG- and IgA-expressing B lymphocytes of female carriers. IgM-, IgG- and IgA-expressing B lymphoblastoid cells (BLC) were established by Epstein-Barr virus transformation of peripheral blood mononuclear cells of two female XHM carriers. In an analysis of differential methylation of the polymorphic DXS255 loci, random X chromosome inactivation patterns were found in populations of T lymphocytes, in IgM-expressing B lymphocytes and in IgG- or IgA-expressing B lymphocytes. The heterogeneity of Ig H chain rearrangements and the Ig light chain usage in the IgA- or IgG-expressing BLC clones that had inactivated the X chromosome which carries the intact XHM gene and in BLC clones with the homologous X chromosome inactivated were similar. The results indicated that the intrinsic Ig H chain class switch mechanism in XHM B lymphocytes is fully intact. We conclude that the XHM gene encodes a class switch inducer that is transferred to B lymphocytes.
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PMID:Evidence that in X-linked immunodeficiency with hyperimmunoglobulinemia M the intrinsic immunoglobulin heavy chain class switch mechanism is intact. 198 Jan 11

Six human immunodeficiency diseases have been associated with the X chromosome by family studies. Genetic mapping with restriction fragment length polymorphisms (RFLPs) has permitted assignment of these diseases to specific loci on the X chromosome. Each of the disease entities maps to a single locus, confirming that the diagnostic criteria describe single diseases. X-linked chronic granulomatous disease and Wiskott-Aldrich syndrome map to loci on the short arm of the X chromosome; X-linked severe combined immunodeficiency, X-linked agammaglobulinemia, X-linked immunodeficiency with hyper-IgM, and X-linked lymphoproliferative syndrome map to loci on the long arm. Lyon's hypothesis predicts that these X-linked immunodeficiencies may be detectable in carriers of the diseases as a result of X chromosome inactivation of the normal disease gene. Four of the immunodeficiency diseases, X-linked agammaglobulinemia, X-linked severe combined immunodeficiency (SCID), Wiskott-Aldrich syndrome, and X-linked chronic granulomatous disease, affect cellular development so that carriers have a monomorphic population of immunocytes. The specific immunocyte development affected in carriers varies according to the disease. Genetic mapping of the diseases, with a collection of informative RFLPs, provides a tool that permits probability-based prenatal diagnosis. Carrier detection complements the RFLP-based genetic mapping, serving to confirm X-linkage in carriers.
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PMID:X chromosome linked immunodeficiency. 198 31

The only molecular defect reported for the X-linked immunodeficiency Wiskott-Aldrich syndrome (WAS) is the abnormal electrophoretic behavior of the major T lymphocyte sialoglycoprotein CD43. Since the 70 to 80 O-linked carbohydrate chains of CD43 are known to influence markedly its electrophoretic mobility, we analyzed the structure and the biosynthesis of O-glycans of CD43 in lymphocytes from patients with WAS. Immunofluorescence analysis with the carbohydrate dependent anti-CD43 antibody T305 revealed that in 10 out of the 12 WAS patients tested increased numbers of T lymphocytes carry on CD43 an epitope which on normal lymphocytes is expressed only after activation. Other activation antigens were absent from WAS lymphocytes. Western blots of WAS cell lysates displayed a high molecular mass form of CD43 which reacted with the T305 antibody and which could be found on in vivo activated lymphocytes but was absent from normal unstimulated lymphocytes. To examine the O-glycan structures, carbohydrate labeled CD43 was immunoprecipitated and the released oligosaccharides identified. WAS lymphocyte CD43 was found to carry predominantly the branched structure NeuNAc alpha 2----3Gal beta 1----3 (NeuNAc alpha 2----3Gal beta 1----4G1cNAc beta 1----6) GalNAcOH whereas normal lymphocytes carry the structure NeuNAc alpha 2----3Gal beta 1----3 (NeuNAc alpha 2----6) GalNAcOH. Only after activation NeuNAc alpha 2----3Gal beta 1----3 (NeuNAc alpha 2----3Gal beta 1----4GlcNAc beta 1----6) GalNAcOH becomes the principal oligosaccharide on CD43 from normal lymphocytes. Analyzing the six glycosyltransferases involved in the biosynthesis of these O-glycan structures it was found that in WAS lymphocytes high levels of beta 1----6 N-acetyl-glucosaminyl transferase are responsible for the expression of NeuNAc alpha 2----3Gal beta 1----3 (NeuNAc alpha 2----3Gal beta 1----4GlcNAc beta 1----6) GalNAcOH on CD43. The gene responsible for WAS has not yet been identified but the results presented in this study suggest that the primary defect in WAS may affect a gene which is involved in the regulation of O-glycosylation.
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PMID:Altered O-glycan synthesis in lymphocytes from patients with Wiskott-Aldrich syndrome. 203 71

The elucidation of B lymphocyte development has been partially achieved through genetic models such as the X-linked immunodeficiency (xid) mutation. We discovered a unique B lymphocyte developmental defect in strain A/WySnJ mice. We used single- and two-color flow cytometry to analyze lymphocytes from A/J and A/WySnJ mice. Adult A/WySnJ mice had a severe B cell deficiency, which was apparent in the spleen, lymph nodes, peritoneum and peripheral blood, compared to adult A/J mice. An ontogeny study revealed that a developmental defect, inhibiting B lymphocyte maturation or differentiation but not B lymphopoiesis, was responsible for the deficiency. This maturational defect blocked the production of B220hi/Iahi/surface IgMlo B cells, and was manifested in the adult bone marrow and neonatal spleen, but not the adult spleen. Neither Ly-1 B cells nor peripheral T cells were apparently affected by the A/WySnJ defect. The B cell immunodeficiency segregated as an autosomal co-dominant trait in F1 and F2 mice. We propose that A/WySnJ mice have a novel genetic defect arresting B cell differentiation in adult bone marrow and neonatal spleen.
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PMID:Phenotypic and genetic characterization of a unique B lymphocyte deficiency in strain A/WySnJ mice. 203 9


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