[X-chromosome recessive lymphoproliferative disease (XLP): molecular genetic studies].

X-linked lymphoproliferative disease (XLP) is a rare worldwide occurring inherited immunodeficiency which is triggered by Epstein-Barr virus infection. Clinical phenotypes in 21 affected males from 5 German families with XLP ranged from severe and fatal infectious mononucleosis (57%) to acquired hypogammaglobulinaemia (28%), malignant lymphoma (28%), aplastic anaemia (19%) and hypergammaglobulinaemia M (19%). Molecular genetic studies with various polymorphic X-chromosomal DNA markers in 14 XLP families mapped the XLP gene locus to Xq25-q26. Haplotype analysis enables detection of XLP-positive and XLP-negative males already before EBV-infection as well as diagnosis of healthy female carriers within XLP families.