Females with a disorder phenotypically identical to X-linked agammaglobulinemia.
Clinical and laboratory findings in two girls with a disorder phenotypically indistinguishable from typical X-linked agammaglobulinemia (XLA) are described. To examine the possibility that subtle defects in the X chromosome might explain the findings, detailed genetic studies were performed on one of these patients. Cytogenetic studies showed a normal 46XX karyotype. Southern blot analysis of her DNA showed that she had inherited a maternal and a paternal allele at sites flanking the locus for typical XLA at Xq22, making a microdeletion or uniparental disomy unlikely. To determine whether both of her X chromosomes could function as the active X, somatic-cell hybrids that selectively retained the active X were produced from her activated T cells. A normal random pattern of X inactivation was seen. Of 21 T-cell hybrids, 3 retained both X chromosomes, 7 had one X as the active X, and 11 had the other X as the active X. We have interpreted these studies as indicating that there is an autosomal recessive disorder that is phenotypically identical to XLA.
Conley
M E
ME
University of Tennessee College of Medicine, Memphis.
Sweinberg
S K
SK
D000361:Agammaglobulinemia / Q000235:genetics* / Q000276:immunology; D000954:Antigens, Surface / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology; D015139:Blotting, Southern; D004247:DNA / Q000032:analysis; D005260:Female; D008040:Genetic Linkage / Q000235:genetics*; D006801:Humans; D007136:Immunoglobulins / Q000276:immunology; D016130:Immunophenotyping; D007223:Infant; D007621:Karyotyping; D008213:Lymphocyte Activation / Q000276:immunology; D013601:T-Lymphocytes / Q000276:immunology; D014960:X Chromosome
D000954:Antigens, Surface; D007136:Immunoglobulins; D004247:DNA