脆性X综合征携带者筛查遗传咨询专家共识

Expert consensus on genetic counselling of carrier screening for fragile X syndrome

脆性X综合征是遗传性智力障碍和孤独症谱系障碍最常见的单基因病,以X连锁不完全显性方式遗传。大约99%的脆性X综合征为FMR1基因CGG扩增动态突变导致,CGG扩增达到前突变或全突变时,可能出现相应的表型。近年来,脆性X综合征携带者筛查在我国逐渐开展起来,遗传咨询能力相对不足。为了更加规范地进行遗传咨询并提供后续生育指导,单基因病携带者筛查共识专家组、中华医学会医学遗传学分会遗传咨询学组通过多次讨论,对脆性X综合征携带者筛查的适用人群、检测前和检测后的遗传咨询内容形成了共识,并通过德尔菲法形成了推荐意见。

Fragile X syndrome is the most common monogenic disorder causing inherited intellectual disability and autism spectrum disorder.It is inherited by an incomplete dominant X-linked fashion.Approximately 99%of fragile X syndrome is caused by the CGG trinucleotide repeat expansion of FMR1 gene,and the corresponding phenotype may appear when CGG expansion reaches pre-mutation or full mutation.Carrier screening of fragile X syndrome has been increasingly undertaken in China,yet the ability of genetic counselling is relatively insufficient.In order to conduct a more standardized genetic counselling and a better fertility guidance,the Consensus Expert Group on Carrier Screening for Monogenic Disorders and Genetic Counselling Group in Society of Medical Genetics,Chinese Medical Association have reached a consensus on the appropriate testing population and the content of pre-and post-test genetic counselling for fragile X syndrome through multiple rounds of discussion and Delphi procedure.