Clinical Research Directory

Natural History Study of Inherited Retinal Diseases

This prospective, observational investigation seeks to delineate the interplay between chromatic vision deficits and both functional visual outcomes and anatomical retinal biomarkers in individuals affected by Inherited Retinal Dystrophies (IRDs). The study will recruit approximately 200 subjects, encompassing a heterogeneous population of IRD patients-spanning a range of genotypes and clinical severities-as well as control participants devoid of retinal pathology. All enrolled individuals will undergo a standardized battery of evaluations, including quantitative color vision assessment, best-corrected visual acuity (BCVA) determination, and advanced multimodal retinal imaging. The principal aim is to characterize the relationship between impairments in color discrimination and morphologic disruptions within the outer retinal layers, with particular emphasis on the continuity and reflectivity of the ellipsoid zone (EZ)-historically referred to as the inner segment/outer segment (IS/OS) junction-assessed through spectral-domain optical coherence tomography (SD-OCT). Further, the study will explore associations between chromatic perceptual deficits and underlying genetic mutations, mutation patterns specific to IRD subtypes, and the influence of patient age on the severity and progression of color vision loss. A key secondary objective is the clinical appraisal and validation of a novel diagnostic modality, the Moji Low-Vision Color Discrimination Test (Moji Test), which is specifically engineered to quantify residual color perception in individuals with advanced central visual impairment. The test's discriminatory capacity will be benchmarked against established color vision testing paradigms to assess its reliability, clinical sensitivity, and suitability for implementation in populations with severe visual acuity reduction. By incorporating a genetically and phenotypically diverse IRD cohort, the study is designed to enable granular, stratified analyses that will refine the understanding of structural-functional correlations in hereditary retinal disease. The inclusion of a control group with preserved retinal architecture and normal color vision function will provide essential normative baselines for comparative evaluation and statistical inference.

Phenotype - Genotype Correlation in a Sample of Egyptian Patients With Congenital Myopathies and Congenital Muscular Dystrophies

The aim of this study is to correlate the phenotype and genotype among a sample of Egyptian patients with Congenital myopathies and Congenital muscular dystrophies.

Prevalence of Lower and Upper Incisor Periodontal Phenotypes and Risk Indicators.

The determination of the periodontal phenotype is an essential part of the periodontal diagnostic process, which must guide not only treatment but also prognosis (Kim et al. 2020). This determination is based on the clinical assessment of 3 individual variables: gingival height/thickness and alveolar bone cortical thickness. Although these anatomical characteristics are genetically determined, they are also influenced by numerous acquired, endogenous or exogenous factors that can act at a general and/or local level. The periodontal phenotype is therefore specific to an individual and its 3 components vary over time according to the dental sectors and sites of each individual. For example, the morphology of this phenotype varies according to whether the gingiva is thick or thin, high or reduced, and the bone cortex is thick or thin, with all possible combinations. Clinicians need to know the distribution of these different types of phenotypes, particularly in the aesthetic areas they are concerned with, in order to better identify the most fragile ones in the face of the multiple daily stresses to which the periodontium may be subjected: muscular force, dental plaque, oral hygiene manoeuvres, parafunctionality, dental procedures.... However, studies on the prevalence of the periodontal phenotype are limited and mainly concern Asian, Indian and American populations, with very few studies on European populations. Main objective: To assess the prevalence of periodontal phenotypes in the upper and lower incisors of French subjects, according to tooth type and at the individual level. Secondary objective: Identification of potential risk indicators in relation to the type of periodontal phenotype."

The Study of the Phenotype of Hereditary Xerocytosis

Hereditary xerocytosis is a dominant red blood cell membrane disorder characterized by an increased leakage of potassium from the interior to the exterior of the red blood cell membrane, leading to water loss, red cell dehydration, and chronic hemolysis. In 90% of cases, it is associated with heterozygous gain-of-function mutations in PIEZO1, a gene that encodes a mechanotransducer responsible for converting mechanical stimuli into biological signals. The remaining 10% of cases are linked to mutations in the GARDOS channel gene.