Variation in the human lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) gene is associated with plasma soluble LOX-1 levels

The lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) expressed on vascular cells plays a major role in atherogenesis by internalizing and degrading oxidized low-density lipoprotein. LOX-1 can be cleaved from the cell surface and released as soluble LOX-1 (sLOX-1), and elevated sLOX-1 levels may be indicative of atherosclerotic plaque instability. We examined associations between the LOX-1 gene 3'UTR-C/T and G501C polymorphisms and plasma sLOX-1 levels in 97 healthy older men and women. The frequencies for the 3'UTR-T and 501C alleles were 46 and 10%, respectively. Plasma sLOX-1 levels were significantly higher in the 3'UTR CC genotype group compared with both the CT (P = 0.02) and TT genotype groups (P = 0.002). Plasma sLOX-1 levels were also significantly higher in the 501GC genotype group compared with the GG genotype group (P = 0.004). In univariate analyses, sLOX-1 levels were significantly associated with both the 3'UTR-C/T and G501C polymorphisms. These associations remained significant after adjusting for age, sex, race and body mass index. In conclusion, variation in the LOX-1 gene is associated with plasma sLOX-1 levels in older men and women.