NCIt definition : An intermediate in the production of thyroid hormones and derivative of tyrosine where
the carbon at position 3 in the benzyl group has been iodinated by thyroid peroxidase.
3-iodotyrosine (mono-iodotyrosine) can be further iodinated by thyroid peroxidase
to form di- and tri-iodo forms. Mono-iodotyrosine can combine with a di-iodotyrosine
to form triiodothyronine (T3) and two di-iodotyrosines can combine to form thyroxine
(T4).;