It was found that 59.52% (n = 50) of hypothyroidism patients (n = 84) had anti-TPO antibodies in their blood circulation suggesting that autoimmunity may play an important role in the pathogenesis of the disease moreover, these autoimmune hypothyroidism patients had significantly increased anti-TPO antibody levels as compared to controls (p<0.0001). This evidence concerns the gene TPO and hypothyroidism.