有三種蛋白，包括甲狀腺素結合球蛋白（TBG）、甲狀腺素和白蛋白，負責攜帶甲狀腺激素甲狀腺素（T4）和3，5，3’-三碘甲狀腺原氨酸（T3）在血流中。該基因編碼血清中主要的甲狀腺激素轉運蛋白TBG在基因組學上屬于serpin家族，但該蛋白與serpin家族的許多其他成員一樣沒有抑制功能該基因突變導致TGB缺乏，根據血清TBG水平分為部分缺乏、完全缺乏和過量另外，還發現了編碼不同亞型的剪接轉錄變體，但尚未確定這些變體的全長性質。[由RefSeq提供，2012年6月]
There are three proteins including thyroxine-binding globulin (TBG), transthyretin and albumin responsible for carrying the thyroid hormones thyroxine (T4) and 3,5,3'-triiodothyronine (T3) in the bloodstream. This gene encodes the major thyroid hormone transport protein, TBG, in serum. It belongs to the serpin family in genomics, but the protein has no inhibitory function like many other members of the serpin family. Mutations in this gene result in TGB deficiency, which has been classified as partial deficiency, complete deficiency, and excess, based on the level of serum TBG. Alternatively spliced transcript variants encoding different isoforms have been found, but the full-length nature of these variants has not been determined.[provided by RefSeq, Jun 2012]