RESUMO
The vast majority of reported (likely) pathogenic missense variants in the genes coding for the fibrillar collagens leads to the substitution of one of the obligatory glycine residues in the Gly-Xaa-Yaa repeat sequence of the triple helical domain. Their phenotypic consequences and deleterious effects have been well-documented. However, with increasing access to molecular diagnostic testing based on next-generation sequencing techniques, such as sequencing of multi-gene panels and whole-exome sequencing, non-glycine substitutions are more frequently identified in individuals suspected to have a heritable collagen disorder, but their pathogenic effect is often difficult to predict.Some specific non-glycine substitutions in the proα1(I)- (p.(Arg312Cys)) and proα1(III)- (glutamic acid to lysine at different positions) collagen chain have been identified in a number of individuals presenting a phenotype showing features of both classical and vascular Ehlers-Danlos syndrome. The number of reported individuals with these defects is currently very low, and several of these non-glycine substitutions had initially been categorised as variants of unknown significance (VUS), complicating early diagnosis, accurate counselling, management guidelines, and correct classification. This collaborative study reports on the phenotype of 22 and 7 individuals harbouring these rare variants in COL1A1 and COL3A1, respectively, expanding our knowledge on clinical presentation, phenotypic variability, and natural history, and informing on the risk for potentially life-threatening events, such as vascular, gastro-intestinal, and pregnancy-related complications.
Assuntos
Cadeia alfa 1 do Colágeno Tipo I , Síndrome de Ehlers-Danlos , Colágeno , Colágeno Tipo III/genética , Síndrome de Ehlers-Danlos/complicações , Síndrome de Ehlers-Danlos/diagnóstico , Síndrome de Ehlers-Danlos/genética , Humanos , Mutação , FenótipoRESUMO
OBJECTIVE: The European Reference Network on Rare and Complex Connective Tissue and Musculoskeletal Diseases involves health care providers (HCPs) from 8 European countries and 7 patients' representatives of European Patient Advocacy Groups. The objective was to evaluate current practice and unmet needs for patient education (PE) in Europe. METHODS: A questionnaire was sent to HCP members asking about the PE practices and another, to enquire about their needs, was sent to patients' associations in the different countries. RESULTS: The questionnaire was completed by 33 HCPs. Half had no specific staff members dedicated to PE. For HCPs with dedicated staff, 83.3% (n = 11) considered that care providers were insufficient to meet patients' needs. Most of HCPs would like to see the practice of PE standardized. Sixty eight percent (n = 1093) of patients suffering from connective tissue diseases completed the questionnaire had never heard about PE. Most of them were interested in taking part in a PE program. DISCUSSION: Our survey revealed a strong interest in PE among patients and HCP and heterogeneity of practice. PE appeared important for both HCPs and patients. An online course for medical students in Europe will be developed in partnership with EULAR to respond to these unmet needs.