A molecular linkage analysis in 11 families with X-linked agammaglobulinemia (XLA) localized the XLA gene to the proximal part of the long arm of the human X chromosome.
As far as X-linked agammaglobulinaemia is concerned, it is now clear that this is a disease of B lymphocytes, and that expression of the XLA gene prevents B cell development beyond the pre-B cell stage.
There is no evidence that the XLA gene is directly involved in the Ig gene rearrangements since B lymphoblastoid cell lines (BLCLs) established from peripheral blood of XLA patients were found to produce IgM molecules composed of complete Ig heavy and light chains and were shown to contain normal VHDJH recombinations.
Mutation analysis of the Bruton's tyrosine kinase gene in X-linked agammaglobulinemia: identification of a mutation which affects the same codon as is altered in immunodeficient xid mice.
A single XLA patient with torsion dystonia and cosegregating X-linked deafness has been found with a deletion in the 3' part of BTK extending centromerically into the flanking expressed sequence DXS1274E.
These studies document the considerable variability in the Btk mutations causing XLA and they demonstrate an approach that will be useful for carrier detection as well as mutation identification.
These studies document the considerable variability in the Btk mutations causing XLA and they demonstrate an approach that will be useful for carrier detection as well as mutation identification.
These studies document the considerable variability in the Btk mutations causing XLA and they demonstrate an approach that will be useful for carrier detection as well as mutation identification.
Mutations in the Btk sequence can cause the human disease X-linked agammaglobulinemia and reasons for the disease in Btk SH2 mutations were inferred from the model.
The gene mutated in the human disease, X-linked agammaglobulinemia (XLA), is related to the Src gene family of cytoplasmic protein-tyrosine kinases and is designated Btk (Bruton's agammaglobulinemia tyrosine kinase; formerly Atk/Bpk; the human gene is denoted BTK, using capital letters according to the kinase nomenclature).