View clinical trials related to Albinism.
Filter by:Albinism is a genetic condition, resulting from mutations in at least 19 known genes responsible for the production of melanin in the skin, hair and eyes. Ophthalmological manifestations are a constant feature of this disease. Albinism is believed to be responsible for 5% of visual impairments worldwide and all albino patients have some degree of fovea plana. In the milder forms, it is a slightly less marked foveolar depression with conservation of the normal diameter of the cones and, therefore, good visual function. In addition to its known association with various ocular pathologies such as albinism, aniridia, nanophthalmia and retinopathy of prematurity, fovea plana was found in 3% of a population of normal children (without known ocular or systemic pathology) in a study conducted in 2014 to determine a pediatric normative basis for macular volume measured by optical coherence imaging (Stratus OCT). More recently, a study carried out at the Hospital Foundation Adolphe de Rothschild showed that at least 35% of parents of albino children, who are totally asymptomatic, present with fovea plana in OCT. This frequency is higher than the 3% prevalence of fovea plana in asymptomatic subjects without a family history of albinism, suggesting a modulation of heterozygosity for a known gene for albinism. The aim of this study is to verify, in patients with fortuitously discovered fovea plana (preoperative OCT for cataract surgery), with conservation of visual function and without known or manifest albinism, whether they are carriers of mutation in one of the genes referenced for albinism. This will also allow us to characterize these foveolar profiles in OCT according to the classification of Thomas et al., as well as in terms of retinal capillary density in OCT-Angiography, in order to know whether it is the same type of fovea plana or if the phenotype differs depending on the genetic damage.
The oculocutaneous albinism is an autosomal recessive condition associated with mutations in 4 genes. In 20% of patients no mutation is identified. The optimization of genetic analysis methods and the search for new genes involved will help improve the diagnosis in these patients.
Fovea plana could be the phenoyipic translation of a genetic anomaly in one of the genes identified in albinisme
The LUVIA study is a randomized placebo-controlled trial designed to investigate the effects of lutein and zeaxanthin supplementation on macular pigment and visual function in ocular or oculocutaneous albinism. Lutein and zeaxanthin supplementation will be compared to a placebo (no treatment) gel pill over the period of 12 months, with study visits approximately every 3 months for the first year and a final visit 18 months after enrollment.
Background: - Oculocutaneous albinism, type 1B (OCA1B) is a genetic disease caused by problems in the gene that makes tyrosine. Tyrosine is an amino acid needed to produce pigment in the skin, hair, and eyes. People with OCA1B have pale skin, white hair, and light-colored eyes. Pigment in the back of the eye helps vision, so people with OCA-1B often have visual problems. Researchers want to see if a drug called nitisinone can help improve eye pigmentation and vision in people with OCA1B. Nitisinone is approved for treating a related genetic disease that causes problems with tyrosine, so it may help people with OCA1B. Objectives: - To see if nitisinone can help improve eye pigmentation and vision in people with OCA1B. Eligibility: - Individuals at least 18 years of age who have OCA1B. Design: - This study will last about 18 months. It requires eight outpatient visits, each about 3 months apart. Each visit will require 1 to 2 days of testing. - Participants will be screened with a physical exam, eye exam, and medical history. They will have additional vision and neurological tests. They will be tested to see how their brain and retinas respond to light. They will also take hair and blood samples, and answer questions about diet. - Participants will receive the study drug. They will take one pill a day for 1 year. They will keep track of the dose in a study diary. - At the outpatient visits, participants will have the following tests: - Medical history and physical exam - Neurological and eye exams - Retina function tests - Tests of the skin and brain's response to light - Blood and urine tests - Dietary consultation - Visual function questionnaire. - After the end of the study, participants will return to the care of their regular eye doctor.
This project will evaluate the effect of two doses of levodopa (L-DOPA) in a randomized, placebo-controlled, double-masked clinical trial to see if vision can be improved in individuals with albinism. The hypothesis is that providing L-DOPA to the retinas of these individuals may increase melanin pigment production. Increased melanin has previously been shown to be associated with improved vision.
Oculocutaneous albinism (OCA) is a term used to describe inherited forms of hypopigmentation associated with 1) variable levels of cutaneous hypopigmentation, ocular hypopigmentation, and visual deficits, and 2) involvement of both of the major developmental types of pigmented cells, i.e., melanocytes and retinal pigment epithelium. OCA that affects only usually-pigmented tissues is termed isolated OCA. There are currently seven albinism types (OCA-1 to OCA-7). With the exception of OCA-5, eash is associated with a specific gene and is inherited in an autosomal recessive manner OCA-5 is a proposed type of albinism associated with the chromosomal location 4q24. OCA-1 results from defects in the enzyme tyrosinase, which catalyzes the rate-limiting step in melanin synthesis. The precise functions of the remaining genes are not yet fully understood, but several may be associated with the regulation of pH in the subcellular organelle where melanin in manufactured-the melanosome. The majority of persons with OCA have two pathogenic mutations identified in a known OCA-causing gene, but a substantial minority to not. Ocular albinism (OA) is an X-linked disorder caused by mutations in the GPR143 gene. It affects the eye in a manner similar to OCA, but has minimal or no skin manifestations. In this protocol, we have four major goals: 1. To clinically and comprehensively characterize OCA types 1 - 7, and OA, with respect to the degree of hypopigmentation, genetic mutations, extent of ocular involvement, and longitudinal variation. 2. To use study participants cultured melanocytes to study pigment biology, variability in pigment formation related to genotype, and response to proposed treatments. Some of this work will be performed collaboratively. 3. To recruit study participants with hypopigmentation not due to known albinismcausing genes. 4. To evaluate methods of quantifying eye pigmentation, skin pigmentation and other clinical parameters that may be usable as outcome measures in future treatment studies. To achieve those goals, we will perform clinical evaluations of persons with OCA and OA at the NIH Clinical Center; obtain cultured cells, plasma, serum and urine for future studies; and, perform mutation analysis on known OCA and/or OA genes and search for other genes responsible for albinism. Routine admissions will last 3 - 4 days and occur every 2 - 3 years.
Hermansky-Pudlak Syndrome (HPS) is an inherited disease that results in decreased pigmentation (oculocutaneous albinism), bleeding problems due to a platelet abnormality (platelet storage pool defect), and storage of an abnormal fat-protein compound (lysosomal accumulation of ceroid lipofuscin). The disease can cause poor functioning of the lungs, intestine, kidneys, or heart. The most serious complication of the disease is pulmonary fibrosis and typically causes death in patients 40 - 50 years old. The disorder is common in Puerto Rico, where many of the clinical research studies on the disease have been conducted. Neither the full extent of the disease nor the basic cause of the disease is known. There is no known treatment for HPS. The drug pirfenidone blocks the biochemical process of inflammation and has been reported to slow or reverse pulmonary fibrosis in animal systems. In this study researchers will select up to 40 HPS patients diagnosed with pulmonary fibrosis. The patients will be randomly divided into 2 groups. The patients will not know if they are taking pirfenidone or a placebo "sugar pill". 1. Group one will be patients who will receive pirfenidone. 2. Group two will be patients who will receive a placebo "sugar pill" The major outcome measurement of the therapy will be a change in the lung function (forced vital capacity). The study will be stopped if one therapy proves to be more effective than the other.
To study the relationship between visual function and ocular (iris, retina/choroidal) pigmentation in patients with albinism and other hypomelanotic disorders. To identify the carrier state in relatives of patients with ocular albinism.