Sera from patients with rheumatoid arthritis (RA) were from the very start
instrumental in detecting and delineating the human immunoglobulin (Ig) all
otypes in the Gm system. Knowledge that human Ig production is under Mendel
ian control and not determined by templates of antigen would not have come
to the fore if it were not for RA patients. Worldwide experience shows that
RA patients are prone to mount an immune response to human Ig allotypes. M
ajor Gm allotypes are defined at the amino acid and nucleotide levers. Gene
technology has been developed for defining these allotypes. Studies of the
Gm allotypes and anti-Gms have led to two apparently paradoxical findings:
(1) In conflict with Mendelian law, non-nominal or hidden allotypes have b
een observed and recently documented at the DNA level. (2) In RA, an immune
response to other individuals' Mendelian allotypes is prevalent, although
RA is generally considered an autoimmune disease. These findings led us to
conclude that RA is not initially an autoimmune disease but a gene transfer
disease. A brief review of viral high-jacking and transfer of human genes
is given along with reasons for considering the herpesvirus family in parti
cular. Genes determining incompatible Ig allotypes are transferred. We have
shown that these genes are expressed in RA synovia. Ig-anti-Ig complexes a
rise and may have arthritogenic potential, as observed in serum sickness.