My feet & ankles are swollen, hot and reddish color. I have high blood pressure, lupus, asthma, back problems, diabetic, fibromyalgia, and Padgett disease, an enlarged heart, and enlarged thymus gland.
1 Free T4 (Free Thyroxine) â considered a precursor hormone, T4 is converted to T3 as required by cells throughout the body; levels of T4 are generally much higher than T3.  Total T4 (Total Thyroxine) - Most T4 in the blood is bound to carrier proteins which make it biologically inactive. Total T4 includes unbound (free) T4 plus T4 that is bound to carrier proteins in the blood.
Biology. 1  The HBB gene codes for haemoglobin, a protein in red blood cells that carries oxygen around the body. 2  A mutation in HBB results in a change in one of the bases in the DNA sequence from an A to a T. 3  This then changes the amino acid in the haemoglobin protein from glutamic acid to valine.