(A) A schematic of the TRIB3 gene 5’ region showing the location of VNTR, containing 3 copies of the 33-bp repeat as in the human reference genome (GRCh38). (B) PCR analysis of the TRIB3 promoter 33-bp repeat copy number in human cell lines. The DNA of hepatocellular carcinoma (HepG2), colorectal adenocarcinoma (Colo205), non-small cell lung carcinoma (H1299), osteosarcoma (SaOS2) and chronic myelogenous leukemia (K562) was amplified using primers flanking the VNTR and the products were separated by agarose gel electrophoresis. (C) Human TRIB3 promoter 33-bp VNTR allele frequencies in Estonian Biobank participants, based on whole genome sequencing data. (D) PCR analysis of the 33-bp repeat copy number in a selection of Estonian Biobank participants. The DNA was analyzed as in panel B, and HepG2 is shown as a control. Lane M in panels B and D contains a molecular weight marker (100 bp DNA ladder).