摘要目的:分析一个家族性腺瘤息肉病(familial adenomatous polyposis，FAP)家系的临床特点及致病变异。方法:收集患者的临床信息，采集外周血样提取DNA，进行全外显子组测序，并通过Sanger测序对候选变异进行验证。结果:先证者为女性，33岁，发现多发腺瘤性息肉。基因检测提示其 APC基因存在c.1922dupA(p.N641fs*10)杂合变异，既往未见报道。根据美国医学遗传学与基因组学学会指南，判断为可能致病。 结论:c.1922dupA(p.N641fs*10)变异可能是该家系的遗传学病因。上述发现有助于对该家系进行遗传咨询。

abstractsObjective:To analyze the clinical features and genetic basis for a Chinese pedigree affected with familial adenomatous polyposis (FAP).Methods:Clinical information of the patient was collected. Genomic DNA was extracted from peripheral blood sample of the patient and subjected to whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing.Results:The proband, a 33-year-old female, was found to have multiple adenomatous polyps in the intestine. WES revealed that she has harbored a heterozygous variant of the APC gene, namely c. 1922dupA (p.N641fs*10), which was unreported previously. Based on the guidelines of the American College of Medical Genetics and Genomics, the variant was predicted to be likely pathogenic. Conclusion:The c. 1922dupA (p.N641fs*10) variant of the APC gene probably underlay the FAP in this pedigree. Above finding has enabled genetic counseling for this family.