Participants, who were classified as either NNG (n = 17), hypothyroidism (n = 14), or control (n = 31), provided serum thyroglobulin (Tg) and completed a semiquantitative iodine food frequency questionnaire. Results. Elevated serum Tg values (Tg > 60 ng/mL) were significantly more prevalent in the NNG group than in the other groups (29% versus 7% and 0% for hypothyroidism and controls, resp., P < 0.05). The gene discussed is TG; the disease is hypothyroidism.