TMEM38B and osteogenesis imperfecta: Moreover, the average serum levels of sclerostin were detected to be significantly higher in the selected OI patients with different gene mutations (n = 2 for WNT1, n = 1 for TMEM38B, n = 1 for FKBP10 and n = 2 for BMP1) than those in healthy controls (n = 6), by enzyme-linked immunosorbent assay (Figure 4B).