COL1A1 and osteogenesis imperfecta: This variant is present in highly conserved glycine residues of Gly-X-Y sequence repeats of the triple helical region of the collagen type I α chain, which may be the cause of OI.<h4>Conclusion</h4>This study revealed that the c.1309G>A (p. Gly437Ser) variant in the <i>COL1A1</i> gene may be the genetic cause of fetal OI in this case.