The VUS (c.4123G>A, p.Ala1375Thr) and likely pathogenic (c.2035G>A, p.Gly679Ser) variants were identified de novo in the COL1A1 and COL1A2 genes, respectively, and were associated with clinically moderate signs of type III OI in the patients. This evidence concerns the gene COL1A2 and osteogenesis imperfecta type 3.