Clinical and genetic investigation in patients with permanent congenital hypothyroidism

•Detection of variants was higher in patients with normal-sized gland-in-situ or goiter than those with thyroid dysgenesis.•Permanent congenital hypothyroidism patients with thyroid dysgenesis required higher doses of L-T4 supplementation with age.•Permanent congenital hypothyroidism patients with the DUOX2 variant required relatively lower doses.