Question: What is (are) Bietti crystalline corneoretinal dystrophy ?
Answer: Bietti crystalline corneoretinal dystrophy is an inherited eye disease. Symptoms include crystals in the cornea (the clear covering of the eye); yellow, shiny deposits on the retina; and progressive atrophy of the retina, choriocapillaries and choroid (the back layers of the eye). This tends to lead to progressive night blindness and loss of visual acuity. Bietti crystalline corneoretinal dystrophy is caused by mutations in the CYP4V2 gene and inherited in an autosomal recessive fashion.
Source: GARD

Question: What are the symptoms of Bietti crystalline corneoretinal dystrophy ?
Answer: What are the signs and symptoms of Bietti crystalline corneoretinal dystrophy? The Human Phenotype Ontology provides the following list of signs and symptoms for Bietti crystalline corneoretinal dystrophy. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Severe Myopia 5% Abnormality of blood and blood-forming tissues - Autosomal recessive inheritance - Chorioretinal atrophy - Constriction of peripheral visual field - Marginal corneal dystrophy - Progressive night blindness - Progressive visual loss - Retinal degeneration - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.
Source: GARD