We report the clinical phenotype and genetic findings of two variants in PDE6C underlying achromatopsia (ACHM). Four patients with the variant c.1670G#x3e;A in exon 13 of the PDE6C gene were identified. Additionally, one had compound heterozygous genotype, with two variants in the PDE6C gene, a variant of c.2192G#x3e;A in exon 18 and c.1670G#x3e;A in exon 13. All patients presented the symptomatic triad of decreased visual acuity, severe photophobia, and colour vision disturbances. SD-OCT showed an absence of the ellipsoid zone, creating an optically empty cavity at the fovea in three patients. The patient with the compound heterozygous genotype presented a more severe subfoveal outer retina atrophy. ERG recordings showed extinguished responses under photopic and 30-Hz flicker stimulation, with a normal rod response. We identified two new variants in the PDE6C gene that leads to ACHM.
Case Rep Ophthalmol 2021;12:749–760

中文翻译：

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导致全色盲的 PDE6C 基因中的两个新的致病变异

我们报告了 PDE6C 基础色盲 (ACHM) 中两种变体的临床表型和遗传发现。鉴定了 PDE6C 基因的外显子 13 中具有变异 c.1670G#x3e;A 的四名患者。此外，一个具有复合杂合基因型，在PDE6C 中有两个变体基因，c.2192G#x3e;A 外显子 18 和 c.1670G#x3e;A 外显子 13 的变体。所有患者均表现出视力下降、严重畏光和色觉障碍的三联征。SD-OCT 显示没有椭球区，在三名患者的中央凹处形成了一个光学空腔。具有复合杂合基因型的患者表现出更严重的中心凹下外层视网膜萎缩。ERG 记录显示在明视和 30-Hz 闪烁刺激下反应消失，杆反应正常。我们在PDE6C基因中发现了两个导致 ACHM 的新变体。
Case Rep Ophthalmol 2021；12:749–760