TG and congenital hypothyroidism: The mutation of various genes can lead to hereditary congenital hypothyroidism, for example, paired box gene 8 (PAX8) and thyroid stimulating hormone receptor (TSHR), which are important in thyroid gland development; dual oxidase 2 (DUOX2), solute carrier family 5 member 5 (SLC5A5), thyroglobulin (TG), and thyroid peroxidase (TPO), which are involved in the synthesis of thyroid hormones; and thyroid stimulating hormone beta (TSHB), which has a role in the stimulation of hormone production, and mutations in this gene lead to central hypothyroidism [4].