RESUMO
<p><b>OBJECTIVE</b>To reveal the association of 4G/5G polymorphism in the promoter region of the plasminogen activator inhibitor 1 gene (PAI1) with plasma PAI1 level in deep vein thrombosis (DVT) in Chinese Han ethnic group.</p><p><b>METHODS</b>One hundred and twenty Chinese DVT patients and 120 healthy controls were recruited. The PAI1 promoter 4G/5G polymorphism was detected using polymerase chain reaction (PCR). The antigen of tissue-type plasminogen activator (tPA) or PAI1 was quantified by a commercially available enzyme-linked immunosorbent assay (ELISA) in DVT cases and health controlsì respectively.</p><p><b>RESULTS</b>Neither in the distribution of PAI1 promoter 4G/5G polymorphism nor in the frequencies of 4G and 5G allele was there a difference between two groups. The levels of PAI1 antigen in the carriers of the 4G/4G genotype were significantly higher than those either in the 4G/5G genotype or in the 5G/5G genotype; In the 4G/5G genotype or in the 5G/5G genotype the TG levels are an independently determinant factor of PAI1 antigen levels.</p><p><b>CONCLUSION</b>There is a close relationship of the PAI1 4G/5G polymorphism to its plasma level in deep vein thrombosis in Chinese Han ethnic group, although lack of association between this genetic variation and risk of DVT suggest no major cause-effect pathogenic role of this polymorphism by itself.</p>