Academic dissertation To be presented for public criticism, with the permission of Abbreviations Abstract 1 Introduction 10 1.1 Primary immunodeficiencies (PIDs) 10 1.1.1 X-linked agammaglobulinemia (XLA) 12

X-linked agammaglobulinemia (XLA) results from failure of B lymphocyte development. Immature B cells from a patient with XLA were found to produce truncated mu and delta immunoglobulin H chains encoded by D-JH-C (mu delta). The 5' terminal sequence of cDNA encoding the H chains is composed of D-JH with the characteristic GGTTTGAAG/CACTGTG consensus sequence utilized for VH gene rearrangement up...