Expression of the Thyroglobulin ChEL Domain in Whole Blood of Patients with Thyroid Pathology

The expression of the thyroglobulin (Tg) cholinesterase-like domain (ChEL domain) was detected in whole blood samples from a patient with Graves' disease and a healthy donor. cDNA templates of the TG ChEL domain were synthesized from mRNA isolated from these samples. Using three of the six primer pairs synthesized to amplify human TG cDNA fragments targeting the ChEL domain, four PCR products were obtained and cloned into the pAL2‑T vector. Using PCR and Sanger sequencing, a 900‑bp TG ChEL domain cDNA fragment with three nucleotide substitutions (c.7408C>T, c.7501T>C, and c.7589G>A) was detected in the healthy donor genome. The 900‑bp cDNA fragment from the patient with Graves' disease harbored a single nucleotide substitution c.8071C>T. The expression of these fragments in eukaryotic cell lines may serve as the basis for the production of recombinant Tg peptides in test systems that allow for the comprehensive diagnosis of various thyroid diseases.