[Polymorphism of human thyroxine binding serum globulin (TBG); existence of a new form of serum protein without detectable triiodothyronine binding power].
Two kinds of TBG polymorphism are described in human, one found in deglycosylated TBG from individual blood donors, the other is a genetically determined polymorphism. TBG from plasma samples from a patient with toxic goiter, not autoimmune, (p)TBG, from the patient's mother (m)TBG and from individual donors (n)TBG, were labeled with [125I]T4 or [125I]T3 and submitted to isoelectric focusing (IEF), followed by autoradiography. Three faint [125I]T4 radiolabeled bands were detectable in (p)TBG while four strong [125I]T4 radiolabeled bands were detectable in (m)TBG and (n)TBG), respectively. IEF of the [125I]T3 incubated serum samples resulted in no detectable isoelectric radiolabeled band for (p)TBG while a normal pattern was found in (m)TBG and in (n)TBG, respectively. These data suggest a new intraindividual not linked to sexual chromosome X polymorphism characterized by a loss in hormone binding.
D000328:Adult; D001782:Blood Donors; D006042:Goiter / Q000097:blood; D006801:Humans; D007525:Isoelectric Focusing; D008297:Male; D011110:Polymorphism, Genetic; D011485:Protein Binding; D013975:Thyroxine-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D014284:Triiodothyronine / Q000097:blood*
D013975:Thyroxine-Binding Proteins; D014284:Triiodothyronine
Polymorphisme de la globuline du sérum humain fixant la thyroxine TBG; existence d'une forme nouvelle de protéine sérique sans pouvoir fixateur décelable de triiodothyronine.