A Seoul National University Bundang Hospital (SNUBH) research team has identified the specific genotypes in Koreans that affect the onset of congenital non-progressive night blindness symptoms for the first time.
Night blindness refers to the symptom of being unable to discern objects in the dark because of vitamin A deficiency, drug toxicity, and various retinal diseases or cataracts. While congenital non-progressive night blindness does not progress or worsen, it may cause decreased visual acuity or strabismus. In addition, the symptom is difficult to detect with a general ophthalmic examination.
Notably, in children who do not receive general ophthalmic examination regularly, hospitals often mistake the symptoms for other diseases, such as brain disease or optic nerve abnormality, causing them to undergo wrong examinations such as brain MR.
To solve this problem, researchers have analyzed patients with congenital non-progressive night blindness.
However, no studies have identified the symptoms and genetic characteristics of Korean patients.
The team, led by Professors Woo Sae-joon and Joo Gwang-shik of the Department of Ophthalmology, conducted a study to confirm the pattern of congenital non-progressive night blindness in Koreans and reveal the genetic correlation.
The team conducted the study for 10 years with 19 Korean patients diagnosed with congenital non-progressive night blindness. In the study, the research team confirmed whether there were genes related to changes in vision, strabismus, and eye tremor in patients with congenital non-progressive night blindness.
The researchers confirmed that when NYX and CACNA1F genes were present, there was a high correlation with decreased visual acuity, strabismus, and eye tremor.
They expect that if the genes are found in the immediate family of a patient with congenital non-progressive night blindness or a child with the above symptoms, the hospital will find an appropriate treatment method and preserve their eyesight early.
“The NYX and CACNA1F genes, which are common in Korean patients with congenital non-progressive night blindness, adversely affect vision as they affect cells that transmit light signals,” Professor Joo said. “Because it can occur even without a special family history, we recommend patients to undergo a genetic test if they have symptoms such as night blindness, glare, or amblyopia.”
Professor Woo also said, “This study is significant in that it is the first study to identify the clinical and genetic aspects of congenital night blindness in Koreans.”
Woo added their team expects that this study will help early diagnosis and treatment development.
The research results were recently published in Genes, a leading academic journal in genetics and genomics.