What is the definition of Fish-Eye Disease?

Fish-eye disease, also called partial LCAT deficiency, is a disorder that causes the clear front surface of the eyes (the corneas) to gradually become cloudy. The cloudiness, which generally first appears in adolescence or early adulthood, consists of small grayish dots of cholesterol (opacities) distributed across the corneas. Cholesterol is a waxy, fat-like substance that is produced in the body and obtained from foods that come from animals; it aids in many functions of the body but can become harmful in excessive amounts. As fish-eye disease progresses, the corneal cloudiness worsens and can lead to severely impaired vision.

What are the causes for Fish-Eye Disease?

Fish-eye disease is caused by mutations in the LCAT gene. This gene provides instructions for making an enzyme called lecithin-cholesterol acyltransferase (LCAT).

The LCAT enzyme plays a role in removing cholesterol from the blood and tissues by helping it attach to molecules called lipoproteins, which carry it to the liver. Once in the liver, the cholesterol is redistributed to other tissues or removed from the body. The enzyme has two major functions, called alpha- and beta-LCAT activity. Alpha-LCAT activity helps attach cholesterol to a lipoprotein called high-density lipoprotein (HDL). Beta-LCAT activity helps attach cholesterol to other lipoproteins called very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL).

LCAT gene mutations that cause fish-eye disease impair alpha-LCAT activity, reducing the enzyme's ability to attach cholesterol to HDL. Impairment of this mechanism for reducing cholesterol in the body leads to cholesterol-containing opacities in the corneas. It is not known why the cholesterol deposits affect only the corneas in this disorder. Mutations that affect both alpha-LCAT activity and beta-LCAT activity lead to a related disorder called complete LCAT deficiency, which involves corneal opacities in combination with features affecting other parts of the body.

How prevalent is Fish-Eye Disease?

Fish-eye disease is a rare disorder. Approximately 30 cases have been reported in the medical literature.

Is Fish-Eye Disease an inherited disorder?

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

  • Condition: Retinitis Pigmentosa
  • Journal: The Cochrane database of systematic reviews
  • Treatment Used: Vitamin A and Fish Oils
  • Number of Patients: 944
  • Published —
In this study, researchers evaluated the safety and effectiveness of vitamin A and fish oils for the prevention of the progression of retinitis pigmentosa.
  • Condition: Atherosclerosis, Acute Coronary Syndrome, and LCAT Deficiency Disorders
  • Journal: Current opinion in lipidology
  • Treatment Used: Cholesterol Acyltransferas (LCAT)-Based Therapeutic Approaches
  • Number of Patients: 0
  • Published —
This article reviewed the use of lecithin cholesterol acyltransferas (LCAT)-based therapeutic approaches in the treatment of atherosclerosis (clogged arteries), acute coronary syndrome, and lecithin:cholesterol acyltransferas deficiency disorders.
Clinical Trial
  • Status: Active, not recruiting
  • Phase: N/A
  • Intervention Type: Drug, Dietary Supplement
  • Participants: 25875
  • Start Date: July 2010
Dry Eye Disease in the Vitamin D and Omega-3 Trial (VITAL)