Aryan Hajar, Bahadori Atekeh, Farhud Dariush D, Zarif Yeganeh Marjan, Pourkalhor Haniyeh
Farhud Genetic Clinic, Tehran, Iran.
Applied Biotechnology Research Center, Tehran Medical Sciences, Islamic Azad University, Tehran, Iran.
Iran J Public Health. 2020 May;49(5):995-1000.
Oguchi disease is a rare autosomal recessive form of congenital stationary night blindness (CSNB) characterized by specific features such as golden-brown discoloration of the fundus called Mizuo-Nakamura phenomenon which is distinguishable by fundoscopy, and retinography. Clinical diagnosis is confirmed through genetic test. Two known genes in pathogenesis of Oguchi disease are and GRK1. A 35-year-old Iranian male exhibiting the clinical features of congenital stationary night blindness, was referred to the genetic clinic of Dr. Farhud, Tehran, Iran in 2012 and examined. Ophthalmic examination including slit-lamp biomicroscopy, perimetry and funduscopy was performed. Additionally, the full-field electroretinography and molecular testing for congenital stationary night blindness were performed. Molecular genetic tests, including the analysis of and genes exon-intron boundaries were performed for this patient and his family. According to the sequencing results, we did not find any mutation in gene. However, a new homozygote mutation at location chr2:233320735, c.517delC, p.P96LfsX28 was identified in exon four of gene. This deletion causes a frame shift mutation, and premature stop codon that results in deletion of about 281 amino acid residues of S-antigen visual arrestin protein (from entire C-terminal). This mutation was also found in patient's parents and one of his sister as heterozygote form. This is the first molecular evidence for gene mutation in an Iranian family affected with Oguchi disease type 1. The identification of the new c.517delC, p.P96LfsX28 mutation in this family with Oguchi disease can confirm the pathogenicity of this variant.
小口病是一种罕见的常染色体隐性先天性静止性夜盲症（CSNB），其特征为特定表现，如眼底出现金棕色变色，即水尾 - 中村现象，通过眼底镜检查和视网膜造影可辨别。临床诊断通过基因检测得以证实。小口病发病机制中已知的两个基因是 和GRK1。一名35岁的伊朗男性表现出先天性静止性夜盲症的临床特征，于2012年被转诊至伊朗德黑兰法尔胡德医生的遗传诊所接受检查。进行了包括裂隙灯生物显微镜检查、视野检查和眼底镜检查在内的眼科检查。此外，还进行了全视野视网膜电图检查和先天性静止性夜盲症的分子检测。对该患者及其家人进行了分子遗传学检测，包括对 和 基因外显子 - 内含子边界的分析。根据测序结果，我们在 基因中未发现任何突变。然而，在 基因的外显子4中发现了一个新的纯合突变，位置为chr2:233320735，c.517delC，p.P96LfsX28。这种缺失导致移码突变和过早的终止密码子，从而导致S - 抗原视觉抑制蛋白约281个氨基酸残基缺失（从整个C末端）。该突变在患者父母及其一个妹妹中也以杂合子形式被发现。这是伊朗一个受1型小口病影响的家庭中 基因突变的首个分子证据。在这个患有小口病的家庭中鉴定出的新的c.517delC，p.P96LfsX28突变可以证实该变异的致病性。
