Study of New Mutations in Cone Disorders (INTROCONE)

University Hospital, Lille

Status: Enrolling

Conditions: Cone Dystrophy; Macular Degeneration; Cone Rod Dystrophy; Retinal Dystrophy, Cone-Rod

Treatments: Genetic: Blood and/or skin biopsy

Study type: Observational

Funder types: Other

Identifiers

NCT04658251

2020-A02559-30 (Other Identifier)

2020_66

Details and patient eligibility

About

High throughput sequencing gives the opportunity to improve the genetic diagnosis for patients suffering from retinal dystrophies and specially from cone disorders. However, a large number of mutations are identified, mostly in introns of the genes, and in silico analysis are not sufficient to assign the pathogenicity of these mutations, without which the diagnosis confirmation cannot be done. For that purpose, a functional analysis of intronic variants of unknown significance detected in patients, with minigene splice assays in parallel with the analysis of the effect of the variant on splicing directly in the cells of the patient, by analyzing the RNA from leucocytes, fibroblasts, lymphoblastoïd cells or precursor of photoreceptor cells, which is the only proof of pathogenicity for variants

Enrollment: 20 estimated patients

Sex: All

Ages: 3+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• clinical diagnosis of cone disorder
• identification of a variant of unknown significance
• possibility of samplings
• informed consent

Exclusion criteria

• no variant of unknown significance identified
• no informed consent

Trial design

20 participants in 1 patient group

Patients with an intronic variant unknown in a gene implicated in cone disorders.

Treatment:

Genetic: Blood and/or skin biopsy