title: A PCR based X-chromosome inactivation assay for carrier detection in X-linked immunodeficiencies using differential methylation of the androgen receptor gene.
abstract: Carrier detection in X-linked immunodeficiencies (X-SCID, WAS, XLA) relies on the demonstration of non-random X inactivation patterns in blood cell lineages. Only a limited number of cells are available after cell separation methods. PCR-based techniques are therefore necessary to analyze active and inactive X chromosomes. Amplifying a polymorphic CAG repeat in the first exon of the androgen receptor gene after selective digestion of the active X chromosome with a methylation-sensitive restriction enzyme allows to distinguish between the paternal and maternal alleles and to identify their methylation status. DNA from B-, T-lymphocytes and total peripheral leukocytes of normal males, females and obligate carriers of X-linked immunodeficiencies were analyzed. The results of this PCR-based X inactivation assay are concordant with the standard methylation studies at the DXS255 locus using Southern blotting. This PCR assay provides a rapid and informative (heterozygosity > 90%) method in carrier detection of X-linked immunodeficiencies and other X-linked disorders, which show non-random X inactivation in cell lineages from the affected tissues.
authors.affiliation: Institut für Humangenetik, Universität Erlangen, Germany.
authors.forename: B
authors.initials: B
authors.lastname: Schmucker
authors.forename: A
authors.initials: A
authors.lastname: Meindl
authors.forename: H
authors.initials: H
authors.lastname: Achatz
authors.forename: J
authors.initials: J
authors.lastname: Mittermüller
authors.forename: G
authors.initials: G
authors.lastname: Krüger
authors.forename: M
authors.initials: M
authors.lastname: Hergersberg
authors.forename: R
authors.initials: R
authors.lastname: Spiegel
authors.forename: A
authors.initials: A
authors.lastname: Schinzel
authors.forename: B H
authors.initials: BH
authors.lastname: Belohradsky
authors.forename: J
authors.initials: J
authors.lastname: Murken
mesh_terms: D004247:DNA / Q000032:analysis; D004303:Dosage Compensation, Genetic; D005260:Female; D006580:Genetic Carrier Screening / Q000379:methods*; D008040:Genetic Linkage / Q000235:genetics*; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000235:genetics*; D008297:Male; D008745:Methylation; D016133:Polymerase Chain Reaction / Q000379:methods*; D011944:Receptors, Androgen / Q000235:genetics*; D014960:X Chromosome / Q000235:genetics*
chemical_list: D011944:Receptors, Androgen; D004247:DNA