ABCA1 and Schnyder corneal dystrophy: Furthermore, ABCA1-labeled exosomal miR-193b levels were slightly increased (P > 0.05) in the serum of SCD patients and significantly increased (P < 0.05) in the serum of MCI and DAT patients compared with the control group, with the highest expression in DAT patients (P < 0.05) (Figure 6(b)).