OSBPL2 and hearing loss disorder: To find out whether the frameshift mutation in OSBPL2 gene affects lipid metabolism, we next tested the blood lipid level in members of this family with the confirmed genotype for OSBPL2. The results showed that the serum lipid levels of individuals with hearing loss are all within normal range, and are indistinguishable from those of normal individuals as determined by the p value (Table 1), suggesting the redundancy of other OSBP proteins in compensating the defect of OSBPL2 in controlling blood lipid metabolism.