Novel SSR4 gene splice variant leads to congenital disorder of glycosylation, type Iy

Congenital disorders of glycosylation (CDG) are a group of multi-systemic genetic disorders. Over 100 monogenic human diseases were known related with defects in glycosylation process. Defects of SSR4 gene lead to a rare X linked pattern of CDG which has been rarely reported. We reported a Chinese boy with developmental delay, microcephaly, and epileptic seizures. Whole exome sequencing and Sanger sequencing were performed in the family. A novel maternal splice variant c.351+1del in SSR4 gene was identified by trio-exome sequencing, and confirmed by Sanger sequencing.