Graves disease and Hashimoto's thyroiditis are autoimmune thyroid diseases (AITD) in which the genetic contribution is complex. The purpose of this work was to analyze the influence of hsp70 gene polymorphisms on the susceptibility to AITD. The hsp 70-2 and hsp 70-hom polymorphism was analyzed, by PCR-RFLP using PstI and NcoI enzymes, respectively, in 40 patients affected with AITD and 38 related healthy individuals belonging to a large consanguineous family named Akr. The transmission disequilibrium test (TDT) was applied on nuclear families, deduced from the Akr pedigree, with at least one heterozygous parent for each studied polymorphism. The corresponding x2 values for hsp 70-2 and hsp 70-hom were, respectively, of 0.52, p > 0.05 and 2.77, p > 0.05. Our data indicated lack of association between these hsp polymorphisms and AITD in this large family.