Among SSc cases, 67.9% were tested for at least one autoantibody: in more detail, 78.7% were tested for ANA, whereas 61.1% for anti-Scl-70, 49.9% for anti-centromere, 41.5% for anti-RNP and 10.0% for anti-RNAPIII. This evidence concerns the gene BTG3 and systemic sclerosis.