X-linked lymphoproliferative syndrome: from clinical presentation to gene.

X-linked lymphoproliferative syndrome (XLP, also known as Duncan's disease) is characterised by an extreme sensitivity to Epstein Barr Virus (EBV), re sulting in a complex phenotype manifested by severe or fatal mononucleosis, acquired hypogammaglobulinemia and malignant lymphoma. The gene responsibl e for XLP has recently been identified by a positional cloning and a functi onal cloning approach and encodes a small cytoplasmic protein involved in s ignal transduction of T and NK cells. The identification of the XLP gene wi ll permit direct diagnosis of XLP in families with a single affected male. Recent progress in immunobiology and genetics of this primary immunodeficie ncy disease are presented (C) 2000 Editions scientifiques at medicales Else vier SAS.