SNP Shot: Genomic Insights

Bietti crystalline dystrophy is characterized by the buildup of numerous small, yellow or white crystal-like deposits of fatty substances (lipids) in the retina, the light-sensitive tissue at the back of the eye. These deposits cause damage to the retina, leading to a gradual decline in vision.

Individuals affected by Bietti crystalline dystrophy commonly start to experience vision problems during their teenage years or in their twenties. These problems include decreased visual acuity (sharpness of vision) and difficulty seeing in low-light conditions (night blindness). They typically also experience visual field loss, most often affecting their peripheral vision. Impaired color vision can also occur.

The progression of vision problems can vary significantly between the two eyes and among different affected individuals, even within the same family. The rate at which the condition worsens also varies. However, most individuals with Bietti crystalline dystrophy become legally blind by the time they reach their forties or fifties. While most retain some degree of central vision, it is typically blurred and cannot be corrected with glasses or contact lenses. This type of vision impairment, uncorrectable with lenses, is referred to as low vision.

Inheritance:

Bietti crystalline dystrophy follows an autosomal recessive inheritance pattern. This means that an individual must inherit two copies of the mutated gene, one from each parent, to develop the condition. The parents, each carrying one copy of the mutated gene, are usually asymptomatic carriers and do not exhibit any symptoms of the disorder.