Gene polymorphisms of the macrophage migration inhibitory factor and acute pancreatitis.

CONTEXT Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that is released by macrophages and lymphocytes and plays an important pathogenetic role in acute pancreatitis. It is present in large amounts in the serum and ascitic fluid in rats with experimental pancreatitis and its levels are elevated in humans with pancreatitis. Polymorphisms associated with inflammatory joint diseases exist in the promoter region of the macrophage migration inhibitory factor gene that alter its expression. OBJECTIVE We investigated the association of macrophage migration inhibitory factor polymorphisms with acute pancreatitis in a population in the UK. PARTICIPANTS A cohort of 164 patients with acute pancreatitis and 197 healthy controls. MAIN OUTCOME MEASURES The -173 G to C single nucleotide polymorphism and the -794 (CATT) n repeat microsatellite were investigated. Restriction fragment length polymorphism (RFLP) was used to assay the -173 polymorphism and PCR followed by polyacrylamide gel electrophoresis (PAGE) was used for the microsatellite. RESULTS The microsatellite did not show any significant differences in distribution between patients and controls. The -173 GG genotype showed a trend towards reduced frequency seen in patients (P=0.056) and the C allele was significantly over expressed in patients (P=0.025). No differences were observed in subgroups based on severity or aetiology of pancreatitis. CONCLUSIONS The -173 C allele is over expressed in acute pancreatitis, however studies are needed to explore this further. Our distribution of the microsatellite alleles was quite different to a previously reported Caucasian population and needs further study from viewpoint of population genetics.