Table 1

X linked immunodeficiencies

Disorder (year of definition of molecular basis)Chromosomal locationGeneFunction/defectDiagnostic tests
FACS, fluorescence activated cell sorting; IL, interleukin; NK, natural killer cell.
X linked chronic granulomatous disease (1986)Xp21gp91phoxComponent of phagocytic NADPH oxidase-phagocytic respiratory burstNitroblue tetrazolium test gp91phox by immunoblotting
Mutation analysis
X linked agammaglobulinaemia (1993)Xq22Bruton's tyrosine kinase (Btk)Intracellular signalling pathways essential for pre-B cell maturationBtk by immunoblotting or FACS analysis
Mutation analysis
X linked severe combined immunodeficiency (1993)Xq13Common γ chain (γc)Component of IL-2, 4, 7, 9, 15 cytokine receptors; T and NK cell development, T and B cell functionCD154 expression on activated T cells by FACS analysis
Mutation analysis
X linked hyper-IgM syndrome (CD40 ligand deficiency) (1993)Xq26CD40 ligand (CD154)Isotype switching, T cell functionCD145 expression on activated T cells by FACS analysis
Mutation analysis
Wiskott-Aldrich syndrome (1994)Xp11WASPCytoskeletal architecture formation; immune cell motility and traffickingWASP expression by immunoblotting
Mutation analysis
X linked lymphoproliferative (Duncan's) syndrome (1998)Xq25SAPRegulation of T cell responses to EBV and ? other viral infectionsMutation analysis
?SAP expression—under development
Properdin deficiency (1992)Xp21ProperdinTerminal complement componentProperdin levels