目的　对Joubert 综合征进行临床特点和遗传学分析。方法　回顾分析1例确诊的Joubert 综合征患儿的临床 资料。结果　患儿男性， 3个月，双眼不追视、发育落后，四肢肌张力偏低。头颅磁共振示“磨牙征”。 全外显子测序显示患 儿MKS1基因c.1411_c.1412insG及c.44A>G复合杂合突变。Sanger测序验证c.1411_c.1412insG移码突变来自于父亲， 已有报道；c.44A>G错义突变来自于母亲，未见报道，根据ACMG指南为可能致病变异。患儿确诊为Joubert综合征。结论 确诊患儿为Joubert综合征，新发现c.44A>G错义突变。

　Objective　To investigate the clinical and genetic data of a pedigree clinically diagnosed as Joubert syndrome. Method　Clinical data of a patient diagnosed as Joubert syndrome in 2017 was retrospectively analyzed. Whole exome sequencing and sanger sequencing were used to find the causative genes. Results　The 3 months old boy displayed eye movement abnormalities, developmental delay and hypotonia in the four limbs. Cranial MRI showed “molar tooth sign”. The gene sequencing identified a frameshift mutation of c.1411_c.1412insG inherited from his father and a novel missense mutation of c.44A>G in MKS1 gene inherited from his mother. Conclusion　The child has typical clinical features of Joubert syndrome. With Combination of clinical features and gene sequencing, the child was diagnosed as Joubert syndrome.