Rare bone diseases (RBD) raised a growing interest worldwide and draw a great attention of ECTS. Inherited disorders are defined by a prevalence of < 2000 individuals, 80% of them are due to a genetic mutation. The rare bone diseases are mainly due to mutations of genes coding for proteins involved in skeletal development, growth and maintenance of the skeleton. The impact is variable stature insufficiency, pain, deformities, fractures and joint damages. In 2023, the update of the nosology of the genetic skeletal disorders includes 771 diseases and 552 genes, which account for around 5% of all rare diseases. This includes skeletal disorders and also diseases of mineral metabolism, i.e. calcium and phosphate. This large number of disorders highlights the diversity and need of awareness of these diseases in terms of training, guidelines for the management and research.
Great progress has been made the last decade for the diagnosis and treatment of RBD. Diagnosis has been improved by the new technologies as nuclear acid sequencing, which decrease in cost made the availability wider and in an accurate manner. Whole genome sequencing is available in some European countries that will facilitate the discovery of new genes. Several molecules have been approved in Europe and others are in the pipelines of the drug industry.
Now, several challenges need to be met for scientists and clinicians. The identification of new genes or new variants will be to understand the pathogenesis triggered by the variants in bone and other tissues, to understand the bone biology induced at the cell and tissue levels, to describe the mechanism of actions of available drugs and to promote the cellular and gene therapies in the future. The aim of clinical research will be to delineate the clinical and imaging aspects throughout time of each disease that will allow to reach the diagnosis in addition to the genetics. There is a need to describe the long-term effects in bone and joints and the damages in other tissues in adults. Progress should also be focused on the biochemical markers, in order to facilitate the understanding of the function and metabolic pathways of the gene variants. All these aspects should be carried-on in parallel in order to reach the diagnosis, to delineate the severity of the disease and to define the patients to treat with the molecules that will emerge in the future. All these questions could only be addressed through multidisciplinary projects among clinicians, scientists and the patient organizations. As bone diseases are rare, collaborations within European countries are crucial to put our efforts together with other societies, as shown by the fruitful collaboration with ERN-BOND, the European Reference Network on Rare Bone Disorders.
Through the rare bone disease action group, ECTS has launched several initiatives such as guidelines position papers and collaborative works. ECTS combines several areas of basic and clinical expertise, let us take the challenges of rare bone diseases.
February marks Rare Disease Month, and the Rare Bone Disease Action Group of the European Calcified Tissue Society (ECTS) is proud to highlight our ongoing efforts to advance research, education, and care for rare bone conditions.
Our webinar series remains a flagship initiative, bringing together leading researchers, clinicians, and patient advocates to share the latest advancements in rare bone diseases. These webinars foster interdisciplinary dialogue and provide valuable insights into challenges and solutions in the field.
We are also excited to share progress on key projects, including the development of a melorheostosis module within the European Registries for Rare Endocrine and Bone Conditions (EuRREB). This new registry module is designed to improve the collection and harmonization of data for melorheostosis, a rare and complex sclerosing bone dysplasia. By integrating patient data across Europe, the module will enhance research opportunities, support clinical care, and drive forward our understanding of this condition.
In addition, we’ve recently published a consensus paper on harmonizing standards for Osteopetrosis (PubMed link). The Rare Bone Disease Action Group continues to focus on conditions such as mastocytosis, skeletal dysplasias, and rare osteoporosis. By strengthening partnerships across Europe, we aim to accelerate progress and improve outcomes for patients living with these challenging diseases. At this moment the group is finalizing a paper on transition in Rare Bone Diseases where we hope to provide some guidance on patients, caregivers and healthcare providers to arrange a smooth transition of care.
We invite you to join our webinars and engage with our projects. For more information, visit the ECTS Rare Bone Disease Action Group page on the ECTS website.
Let’s use Rare Disease Month as an opportunity to celebrate advancements and reaffirm our commitment to addressing the challenges of rare bone diseases together.