Extremely high frequency of autoimmune-predisposing alleles in medieval specimens

Abstract

The precise etiology and reasons for the increase in incidence of autoimmune disorders still remain unclear, and although both genetic and environmental factors have been proven to shape individual predisposition, it is not known which of the factors, if not both, is responsible for the boom observed during the last decades. In order to establish whether a higher frequency of autoimmune-predisposing alleles may explain this increase we took advantage of ancient DNA methodology to establish the genetic predisposition, conferred by cytotoxic T lymphocyte associated antigen-4 (CTLA4) +49A/G and human leukocyte antigens (HLA) DQB1(57), in population inhabiting Poland in the Middle Ages. After successful typing of 42 individuals from a 12th approximately 14th's century archeological burial site, we found that frequencies of the predisposing alleles in the medieval population were higher than they are at present, suggesting thus that the recently observed incidence increase results most probably from factors of other than genetic nature.

Metabolic and Endocrine Diseases

“…Analysis of aDNA isolated from medieval archaeological sites around Poland showed significantly higher frequency of alleles HLA DQB57 and CTLA-4 ( which are believe to be predisposing to Type 1 diabetes) than in a modern control group (Witas et al 2007;Witas et al 2010). Analysis of aDNA isolated from medieval archaeological sites around Poland showed significantly higher frequency of alleles HLA DQB57 and CTLA-4 ( which are believe to be predisposing to Type 1 diabetes) than in a modern control group (Witas et al 2007;Witas et al 2010).…”