An overwhelming majority of females (72%), in those tested for thyroid antibody, were positive in this study which is in accord with the NHANES III study.7 The Whickham survey reported that a twofold rise in serum TSH would increase the probability of developing overt hypothyroidism from 1to 4%; this risk further increased to 38% if positive for TPO antibodies. This evidence concerns the gene TPO and hypothyroidism.