{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T14:20:14Z","timestamp":1791296414728,"version":"4.1.0"},"reference-count":0,"publisher":"National Academy of Sciences","issue":"20","content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[1989,10]]},"abstract":"<jats:p>IgA deficiency and common variable immunodeficiency are heritable disorders that can occur within the same family. Both immunodeficiencies are characterized by arrests in B-cell differentiation that vary in the extent of the immunoglobulin isotypes involved. A high frequency of major histocompatibility complex supratypes associated with a null allele of the gene encoding the C4A isotype of complement component C4 has been observed in IgA-deficient individuals. In search of a genetic linkage between the two immunodeficiencies, we examined the major histocompatibility complex (MHC) class III genes encoding complement components C2, C4A, and C4B and steroid 21-hydroxylase in addition to the HLA serotypes in individuals with either common variable immunodeficiency or IgA deficiency. Twelve of 19 patients with common variable immunodeficiency (63%, P less than 0.001) and 9 of 16 patients with IgA deficiency (56%, P less than 0.01) had rare C2 alleles and\/or C4A and 21-hydroxylase A deletions, whereas these gene features were seen in only 5 of 34 healthy individuals (15%) in the control group. Nine of 11 patients with C4A deletion had an HLA haplotype consistent with the MHC supratype HLA-A1, Cw7, B8, C4AQ0, C4B1, BfS, DR3 previously found to be associated with IgA deficiency. The data support the hypothesis that common variable immunodeficiency and IgA deficiency are related disorders, susceptibility to which is determined by a gene(s) within or near the MHC class III gene region on chromosome 6.<\/jats:p>","DOI":"10.1073\/pnas.86.20.8015","type":"journal-article","created":{"date-parts":[[2006,5,31]],"date-time":"2006-05-31T07:05:49Z","timestamp":1149059149000},"page":"8015-8019","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":115,"title":["Individuals with IgA deficiency and common variable immunodeficiency share polymorphisms of major histocompatibility complex class III genes."],"prefix":"10.1073","volume":"86","author":[{"given":"F M","family":"Schaffer","sequence":"first","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J","family":"Palermos","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Z B","family":"Zhu","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"B O","family":"Barger","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"M D","family":"Cooper","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J E","family":"Volanakis","sequence":"additional","affiliation":[{"name":"Department of Pediatrics, University of Alabama at Birmingham 35294."}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[1989,10]]},"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.86.20.8015","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,4,13]],"date-time":"2022-04-13T12:47:19Z","timestamp":1649854039000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/full\/10.1073\/pnas.86.20.8015"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1989,10]]},"references-count":0,"journal-issue":{"issue":"20","published-print":{"date-parts":[[1989,10]]}},"alternative-id":["10.1073\/pnas.86.20.8015"],"URL":"https:\/\/doi.org\/10.1073\/pnas.86.20.8015","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[1989,10]]},"assertion":[{"value":"1989-10-01","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}