Abstract
We report a case of a female individual with severe spine osteoporosis diagnosed at age 52. History revealed a childhood diagnosis of spondylometaphyseal dysplasia corner fracture type (SMDCF), a rare skeletal dysplasia associated with short stature and scoliosis. Genetic analysis showed a novel heterozygous variant in the fibronectin 1 gene (FN1) which mapped to 4 affected family members. The site of the familial pathogenic variant (c.643T>C, p.Cys215Arg) was located in the part of the fibronectin protein associated with established pathogenic variants, which interfere with secretion of the protein from mesenchymal stem cells. Little has been reported regarding the natural history of SMDCF: our patient presented to the adult endocrine clinic with early postmenopausal osteoporosis. Her scoliosis was mild, and she admitted to continued limb pain that had been present since childhood.