GM Allotypes and IGG Subclass Concentrations

 GM ALLOTYPES AND IGG SUBCLASS CONCENTRATIONS

Studies from several laboratories have found a correlation between certain GM allotypes or phenotypes and the concentration of the four subclasses of IgG. The results vary; however, virtually all studies report a significant association between the GM 3 5,13 phenotype and a high IgG3 concentration and the G2M 23 allotype and an increased concentration of IgG2. These associations imply that a determination of whether a person’s IgG subclass level is in the “normal” range should be made in the context of the individual’s GM phe-notype.

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