Xiong et al. isolated exosomes from the plasma of persons with coronary heart disease confirmed by coronary angiography and found that, compared to controls, mRNA for sphingosine-1-phosphate receptor 5 (S1PR5) was upregulated and mRNA for carnosine synthase 1 (CARNS1) was downregulated and each were independent risk factors for coronary heart disease [21]. This evidence concerns the gene S1PR5 and coronary artery disorder.