Although the association of anti-Scl-70 antibody and the presence of topoisomerase-I (Scl-70) specific CD4+ T cells in SSc patients has been reported [27], we found that following stimulation by peptides derived from DNA topoisomerase protein, the numbers of IFN-γ and IL-2 secreting CD4+ T cells was comparable in SSc patients with and without anti-Scl-70 antibodies. This evidence concerns the gene IFNG and systemic sclerosis.