Abstract: Objective　To explore the pathogenic gene mutation of a child with West syndrome in a Marfan syndrome family, and to provide the basis for genetic consultation. Methods　The clinical data of the child and her family members were collected and analyzed. Peripheral blood DNA of the child and her parents, maternal grandmother and uncle were extracted. The whole exome next genetic sequencing was employed and copy number variation was detected, and then the result was verified by Sanger sequencing. The relevant literature was reviewed. Results　A 10-month-old girl had recurrent convulsions for 7 months, presenting as infantile spasm. There were signs of Marfan syndrome in the child, her mother and grandmother. There was nonsense mutation of c.7240C>T (p.R2414*) in FBN1 gene in the proband, her mother and the maternal grandmother. Furthermore, a frameshift mutation of c.601delG (p.A201Qfs*148) in SLC35A2 gene was also found in the proband, but no such mutation was found in SLC35A2 gene of the parents. This gene mutation has not been reported before. The thoracic ventricular septal defect repair was performed for the child. After the treatment with topiramate and galactose supplementation, the epilepsy and development of the child were improved. A total of 16 articles on SLC35A2 gene mutation with complete clinical data were retrieved, involving a total of 74 patients and 58 mutation loci, among which missense mutation was the most common. Patients could have different clinical phenotypes, and early infant epileptic encephalopathy was the most common. Conclusions　The SLC35A2 gene c.601delG (p.A201Qfs*148) is a pathogenic variant of West syndrome in Marfan syndrome family. This study expanded the gene mutation spectrum and provided the basis for genetic counseling of the family. Galactose combined with topiramate treatment is helpful to control seizures and improve development.

Key words: 　Marfan syndrome;　West syndrome;　SLC35A2 gene;　mutation