■Oguchi病是一种罕见的常染色体隐性视网膜营养不良,以先天性静止性盲为特征,并由SAG和GRK1基因的致病变异引起。本研究旨在报告一名受Oguchi疾病影响的意大利患者,通过多模式视网膜成像研究进行评估,并在SAG基因中包含两个新的杂合致病变异。
■通过眼底照片调查了一名60岁的女性,该女性抱怨先天性静止性夜盲症,光学相干断层扫描(OCT),视网膜电图(ERG),和基因检测。
■眼底检查显示金灰色眼底。暗位ERG的杆响应无法检测到,混合的杆锥响应是负电性的。在光照和长时间适应黑暗的条件下获得的眼底照片可以检测到Mizuo-Nakamura现象。异常视网膜区域的光条件OCT显示,外光感受器节段层中的高强度区域,随着长时间的黑暗适应而减少。遗传检测确定了SAG基因中的两个罕见的杂合序列变体:NM_000541.5:c.807delAp。(Glu270Lysfs*9)和NM_000541.5:c.1047-1G>C,证实了Oguchi病的诊断。
■我们确定了第一个在SAG基因中具有两个新变化的意大利复合杂合患者(移码缺失和剪接变体)。在日本人群中,SAG基因参与Oguchi病是一个常见的发现,但在白种人中很少发现。临床怀疑应提示与这种情况相关的基因的分子分析。
UNASSIGNED: Oguchi disease is a rare autosomal recessive retinal dystrophy, characterized by congenital stationary blindness and caused by pathogenic variants in SAG and GRK1 genes. The present
study aimed to report an Italian patient affected by Oguchi disease, evaluated by means of a multimodal retinal imaging
study and harboring two novel heterozygous pathogenic variants in the SAG gene.
UNASSIGNED: A 60-year-old female complaining congenital stationary night blindness was investigated through fundus photograph, optical coherence tomography (OCT), electroretinography (ERG), and genetic testing.
UNASSIGNED: Fundus examination showed a golden-grayish fundus aspect. The rod response of the scotopic ERG was undetectable and mixed rod-cone response was electronegative. Fundus photographs obtained in light and in prolonged dark-adapted conditions allowed to detect the Mizuo-Nakamura phenomenon. Light condition OCT over the abnormal retinal regions showed high-intensity areas in the outer photoreceptor segment layer, that reduced with prolonged dark adaption. Genetic testing identified two rare heterozygous sequence variants in the SAG gene: NM_000541.5:c.807delA p.(Glu270Lysfs*9) and NM_000541.5:c.1047-1G>C confirming the diagnosis of Oguchi disease.
UNASSIGNED: We identified the first Italian compound heterozygous patient harboring two novel alterations in the SAG gene (a frameshift deletion and a splicing variant). The involvement of the SAG gene in Oguchi disease is a common finding in Japanese population, but rarely identified in Caucasians. Clinical suspicion should prompt the molecular analysis of genes associated with this condition.