A study also described the loss of the Lys-Asp-Glu-Leu (KDEL) endoplasmic reticulum (ER) retrieval sequence as a consequence of a P3H1 pathogenic variant, which also led to a lack of intracellular P3H1 and type 3 OI [27]. This evidence concerns the gene P3H1 and osteogenesis imperfecta type 3.