患儿，女，7岁，因视力急剧下降就诊。自1岁起，患儿出现发育迟缓，并伴有视力障碍及中性粒细胞减少等表现。结合基因检测及分子致病性研究，患儿最终确诊为VPS13B基因复合杂合变异（c.6940+1G>T和c.2911C>T）所致的Cohen综合征（Cohen syndrome, CS）。c.6940+1G>T导致38号外显子跳跃，引发移码与提前终止。反转录聚合酶链反应结果显示，患儿VPS13B基因表达量显著下降（P<0.05）。生物信息学分析提示上述两种变异均可能导致截短蛋白。该病例提示，结合临床特征与分子致病性评估（DNA、RNA及蛋白质分析）可有效提高CS早期诊断的准确性。

A 7-year-old girl was admitted to the hospital with rapidly progressive vision loss. Since 1 year of age, she had exhibited developmental delay accompanied by visual impairment and neutropenia. Combined with genetic testing and molecular pathogenicity analysis, she was diagnosed with Cohen syndrome (CS) caused by compound heterozygous variants in VPS13B (c.6940+1G>T and c.2911C>T). The c.6940+1G>T variant resulted in exon 38 skipping, leading to a frameshift and premature termination. Reverse transcription quantitative polymerase chain reaction revealed significantly reduced VPS13B gene expression (P<0.05). Bioinformatic analysis suggested that both variants likely produce truncated proteins. This case highlights that integrating clinical features with molecular pathogenicity assessment (DNA, RNA, and protein analysis) can improve early diagnostic accuracy for CS.