Hyper-IgM syndrome type 2

In medicine, Hyper IgM Syndrome Type 2 is a rare disease. Unlike other hyper-IgM syndromes, the Type 2 patients identified thus far did not present with a history of opportunistic infections. One would expect opportunistic infections in any immunodeficiency syndrome. The putative genetic lesion is in the AICDA gene found at 12p13. The patients have three common findings ^[1]:

• the absence of immunoglobulin class switch recombination
• the lack of immunoglobulin somatic hypermutations, and
• lymph node hyperplasia caused by the presence of giant germinal centers.

References

1. ^ [http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Abstract&list_uids=11007475 Activation-induced cytidine deaminase (AID) deficiency causes the autosomal recessive form of the Hyper-IgM syndrome (HIGM2)], Cell. 2000 Sep 1;102(5):565-75.

• Online 'Mendelian Inheritance in Man' (OMIM) 605258