Two Cases of Autosomal Recessive Marinesco-Sjögren Syndrome Caused by SIL1 Gene Mutations

Marinesco-Sjögren syndrome(MSS) is a rare autosomal recessive inherited disease characterized by cerebellar ataxia, early-onset cataracts, chronic myopathy, and intellectual disability and developmental delay at varied degrees. Some patients may manifest such symptoms as short stature, hypergonadotropic hypogonadism, various skeletal abnormalities resulted from the muscular weakness, and others. This article reports the clinical and molecular diagnosis process of two MSS cases with global developmental delay. We found the compound heterozygous variants c.109delG(p.Glu37Serfs*4)and c.353G > C (p.Arg118Thr), c.443delA(p.Lys148Argfs*10)and c.707A > G (p.Asn236Ser) by Trio-whole exome sequencing(Trio-WES)which are evaluated as pathogenic, and uncertain significant, pathogenic and likely pathogenic variants separately.We provided genetic consultation based on the molecular diagnosis and evaluated the risk for the offsprings in the families. By introducing the two cases and literature review, this article aims at improving the understanding of MSS and providing reference to the diagnosis of the disease.