Genetic diagnosis and research in Epidermolis BullosaOngoing
|Project lead||MJ Escámez and M del Río|
|Organisation||CIEMAT - Centro de Investigaciones Energéticas Medioambientales y Tecnológicas|
|Partner organizations & collaborators||CIBER on Rare Diseases |
UC3M – Universidad Carlos III de Madrid
IISFJD – Instituto de Investigación Sanitaria de la Fundación Jiménez Díaz
|Project budget||EUR 100,072.32|
|Start date / Duration||01. Jan 2018 / 32 months|
|Funder(s) / Co-Funder(s)||DEBRA Spain|
|Research area||EB genetics, epigenetics & biology, Symptom prevention & relief|
Publications related to the projectsIdentical COL71A1 heterozygous mutations resulting in different dystrophic epidermolysis bullosa phenotypes Genetic Diagnosis of Epidermolysis Bullosa: Recommendations From an Expert Spanish Research Group Clinical practice guidelines for laboratory diagnosis of EB
Short lay summary
There are 4 main types of Epidermolysis Bullosa (EB simplex, junctional EB, dystrophic EB and Kindler syndrome) and 30 subtypes. People with EB carry mutations in specific gene(s), therefore the glue that keep the layers of the skin (and mucosa) together are missing or malfunctioning. Thus, EB affected have fragility of the skin and mucosa. There are many genes (20) and mutations (more than 1000) involved in EB making diagnosis difficult and costly. To do molecular diagnosis of EB the following is need: 1) a clinical/family history 2) a skin fresh biopsy to establish the cleavage plane, classify the disease among the 4 main types and select candidate gene(s) 3) a blood sample to extract DNA and search for mutation(s) in the candidate gene(s). Molecular diagnosis is mandatory for knowing the precise EB subtype, for genetic counseling (inheritance pattern, risk of recurrence, and options for prenatal and preimplantation diagnosis) and for participation in clinical trials. DEBRA-Spain has financed the hiring of a geneticist for two years for supporting U714-CIBERER to do the diagnosis of epidermolysis bullosa (EB) and an EB expert for 8 months.
Epidermolysis bullosa (EB) is a clinically and genetically heterogeneous group of gendermatosis that causes mucocutaneous fragility. EB is classified into 4 major types (EB simplex, junctional EB, dystrophic EB and Kindler syndrome) and 30 clinical subtypes. EB is caused by defects in proteins implicated in the cohesion of the integument. So far, more than 1000 mutations identified in 20 genes are involved in EB, thus rendering diagnosis complex. Molecular diagnosis of EB that starts with the compilation of a detailed clinical/family history and the procurement of a skin fresh biopsy that includes an area where the epidermis detaches from the dermis to establish the cleavage plane by antigen mapping to identify candidate gene(s) to search for pathogenic mutations in the DNA extracted from a blood sample. Molecular diagnosis provides appropriate genetic counseling (inheritance pattern, risk of recurrence, and options for prenatal and preimplantation diagnosis) and reasonable clinical prognosis. Moreover, molecular diagnosis is essential for the participation of patients in clinical trials, a critical issue given the current incurable status of EB. Since 2007, the Unit 714 at the CIBER of Rare Diseases, carries out the molecular diagnosis of epidermolysis bullosa in Spain. Since then more than 350 affected people have requested diagnosis, being 293 of them diagnosed to date. The diagnosis is performed in collaboration with another groups of CIBERER (S º de Genetics of the Jiménez Díaz Foundation) and DEBRA-Spain. Genetic studies are requested from the reference centers for EB (University Hospital La Paz, in Madrid and Sant Joan de Deu and Clínic Hospitals, in Barcelona) and other hospitals spread throughout the Spanish geography. Given the complexity of EB, its diagnosis is an expensive and laborious process. In the context of this project, DEBRA has financed the hiring of a geneticist for two years for supporting the diagnosis of epidermolysis bullosa (EB) by U714-CIBERER and an EB expert for 8 months.
The support of DEBRA-Spain has improves outcomes in the diagnosis of EB and KS (prognostication, decision-making, genetic counselling) and patient’s enrolment for clinical trials. Next step is the translation of the diagnosis from the research lab to a clinical setting.