DUOX2 and hypothyroidism: Moderate iodine deficiency in association with double heterozygosity for DUOX1 and DUOX2 mutations (S1 and parents) did not result in hypothyroidism (urinary iodine: mother 39.2 μg/L; father 38.7 μg/L; S1 43.1 μg/L; RR 100 to 700 μg/L) (Fig. 1).