CPT® Code 81364

The CPT® Code 81364 pertains to the full gene sequence analysis of the hemoglobin, subunit beta (HBB) gene, which is crucial for diagnosing various hemoglobin disorders. The HBB gene is responsible for encoding the beta-globin protein, a vital component of hemoglobin found within red blood cells (RBCs). Hemoglobin itself is a protein complex made up of two beta-globin and two alpha-globin subunits, with the alpha-globin subunits encoded by the HBA gene. Each of these protein subunits is associated with iron-containing heme molecules that are essential for oxygen transport throughout the body. The HBB gene is located on the short arm of chromosome 11 at position 15.4. Mutations in the HBB gene can lead to significant health conditions, including sickle cell anemia, beta thalassemia, and other hemoglobinopathies. For instance, in sickle cell anemia, a specific mutation results in the substitution of the amino acid glutamic acid with valine at position 6 of the beta-globin subunit, leading to the formation of hemoglobin S (HbS). This abnormal hemoglobin causes red blood cells to adopt a sickle shape, which can obstruct blood flow and lead to various complications. Beta thalassemia is characterized by mutations that either reduce or completely halt the production of beta-globin, resulting in a deficiency of mature RBCs and subsequent oxygen delivery issues. Additionally, methemoglobinemia, a condition associated with the HBB gene, occurs when the normal ferrous iron in hemoglobin is replaced by ferric iron, impairing oxygen binding and leading to symptoms such as cyanosis and fatigue. The full gene sequence testing provided by CPT® Code 81364 is instrumental in identifying specific mutations associated with these disorders, evaluating abnormal hemoglobin types, and conducting preconception screenings for individuals with a family history of hemoglobinopathies. This comprehensive analysis is performed on a blood sample, which is obtained through a separate procedure and analyzed using advanced techniques such as polymerase chain reaction (PCR) and sequencing methods.