A PV c.596G>A (Gly199Asp) at the same amino acid residue of COL1A2 was associated with OI, confirming that Glycine 199 (G199) is an essential residue for COL1A2 function (Figure 2, Clinvar VCV000496615.30, dbSNP 1554395833). This evidence concerns the gene COL1A2 and osteogenesis imperfecta.