HCG is a glycoprotein, which is secreted in large quantities by normal trophoblasts. It is present only in trace amounts in non-pregnant urine and sera but rises sharply during pregnancy. HCG is composed of two non-identical, non-covalently linked polypeptide chains designated as the alpha and Beta subunits. The alpha subunit is identical to that of thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH), and luteinizing hormone (LH).
CG-beta; CGB3, CGB5, CGB7, CGB8, hCGB,CG-beta; Choriogonadotropin subunit beta; Choriogonadotropin subunit beta 3; chorionic gonadotrophin chain beta; chorionic gonadotropin beta 3 subunit; chorionic gonadotropin beta chain; chorionic gonadotropin beta subunit; Chorionic gonadotropin chain beta; chorionic gonadotropin, beta polypeptide