Fractures in the structure of rare hereditary pathology – gnathodiaphyseal dysplasia and Grange syndrome

Abstract

Bone fractures may be observed in various hereditary diseases, including rare ones – gnathodiaphyseal dysplasia and Grange syndrome. We present a description of two patients with frequent fractures: a 12-year-old girl with gnathodiaphyseal dysplasia associated with the previously described c.1538C>T variant in the ANO5 gene, and an 11-year-old boy with new compound heterozygous variants c.1564C>T and c.2117_2118del in the YY1AP1 gene and the Grange syndrome phenotype. Both patients had frequent pathological bone fractures on the background of osteoporosis. Both children had normal intelligence. The phenotype of the child with Grange syndrome included variable fracture localization, moderate brachydactyly, delayed bone age, mitral valve prolapse, labile systolic hypertension, hyperactivity, and attention deficit disorder. In this case particular attention was paid to the cardiovascular system. The patient with gnathodiaphyseal dysplasia predominantly suffered from vertebral fractures. Thus, the presented clinical observations indicate the need to include gnathodiaphyseal dysplasia and Grange syndrome in the differential diagnostic series when osteogenesis imperfecta is suspected.