Eta-1/osteopontin genetic polymorphism and primary biliary cirrhosis

Early T-lymphocyte activation 1 (Eta-1)/osteopontin is a soluble ligand with pleomorphic immunologic activities including activation of macrophage chemotaxis, promotion of Th1 responses, and activation of B1 B-cells. A recent study suggested that a single-nucleotide polymorphism (SNP) at position nt 9250 (C to T) in exon 7 was highly associated with systemic lupus erythematosus (SLE). Eta-1/osteopontin was reported to be highly expressed in the MRL/lpr mouse, which is recognized as one of the spontaneous autoimmune models of SLE. In the present study, we first investigated the association with this SNP and susceptibility to primary biliary cirrhosis (PBC). The allele frequencies of C/C, C/T, and T/T at position nt 9250 on the Eta-1/osteopontin gene in 50 PBC patients were 20, 32, and 48%, respectively, compared with 9, 47, and 44% in 34 healthy controls (P<0.16-0.72). The gene frequencies of C and T at this position in such PBC patients were 0.36 and 0.64, whereas those in the healthy controls were 0.32 and 0.68 (P<0.91), respectively. Moreover, clinical findings and pathologic stages were not correlated with the variation of SNP. Those findings suggest no associations with Eta-1/osteopontin genetic polymorphism and susceptibility to PBC.