Maternal germinal mosaicism of X-linked agammaglobulinemia

Am J Med Genet. 2001 Mar 15;99(3):234-7. doi: 10.1002/1096-8628(2001)9999:9999<::aid-ajmg1159>3.0.co;2-m.

Abstract

X-linked agammaglobulinemia (XLA) is an immunodeficiency caused by abnormalities in tyrosine kinase (BTK), and is characterized by a deficiency of peripheral blood B cells. We studied cytoplasmic expression of BTK protein and analyzed the BTK gene (BTK) in peripheral blood mononuclear cells from two siblings with XLA and additional family members. Cytoplasmic expression of BTK protein in monocytes was not detected in either patient with XLA. A single base deletion (C563) in BTK-exon 6, which encodes the TH domain, was identified in both XLA patients. However, normal cytoplasmic expression of BTK protein in monocytes was detected in their mother without any BTK mutation. These results strongly suggest germinal mosaicism in the mother.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Agammaglobulinaemia Tyrosine Kinase
  • Agammaglobulinemia / genetics*
  • Child
  • Child, Preschool
  • Cytoplasm / enzymology
  • DNA Mutational Analysis
  • Female
  • Genetic Linkage
  • Humans
  • Male
  • Mosaicism*
  • Mothers
  • Mutation
  • Pedigree
  • Protein-Tyrosine Kinases / genetics*
  • X Chromosome*

Substances

  • Protein-Tyrosine Kinases
  • Agammaglobulinaemia Tyrosine Kinase
  • BTK protein, human