Structural and immunologic analysis of gene triplications in the Ig heavy chain constant region locus

A. Brusco, U. Cariota, Andrea Bottaro, C. Boccazzi, A. Plebani, A. G. Ugazio, R. Galanello, A. M. Van Leeuwen, G. G. DeLange, S. Depelchin, A. O. Carbonara

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

The Ig H chain C region is a multigene family often involved in genomic rearrangements leading to deleted and duplicated haplotypes, most probably through unequal crossing over between homologous regions within the locus. The frequency of these haplotypes in Italy is around 2.7% each. Using PFGE analysis in two unrelated Italian families we found an abnormal high m.w. band, inherited in a Mendelian fashion. To assess the extension of the haplotype we performed Southern blot analysis using several specific Ig H chain C probes. In both cases, the haplotype turned out to be triplicated, with three copies of the genes from A1 to E. In one family segregation of a duplication from EP to G4 was also observed. Analysis of polymorphic loci suggests that the two triplications are of independent origin. Serological detection of IgA2 allotypes demonstrated the functional activity of the genes at the 3' end of the triplicated locus, ruling out any major effect of these large genomic rearrangements on Ig class switching. Furthermore, the triplicated haplotype does not seem to give rise to any clinically significant immunological impairment or increase in Ig serum concentrations.

Original languageEnglish (US)
Pages (from-to)129-135
Number of pages7
JournalJournal of Immunology
Volume152
Issue number1
StatePublished - Jan 1 1994
Externally publishedYes

All Science Journal Classification (ASJC) codes

  • Immunology and Allergy
  • Immunology

Fingerprint Dive into the research topics of 'Structural and immunologic analysis of gene triplications in the Ig heavy chain constant region locus'. Together they form a unique fingerprint.

Cite this