Clinical and molecular genetic study of infantile-onset Pompe disease in Chinese patients: identification of 6 novel mutations.

Pompe disease is an autosomal recessive disorder and is caused by a deficiency in acid alpha-glucosidase (GAA). A broad range of studies have been performed on Pompe patients from different countries. However, the clinical course and molecular basis of the disease in Mainland China have not been well defined. In the present study, we examined a total of 18 Chinese children with infantile-onset Pompe disease to better understand the clinical and genetic features in this population. The median age at symptom onset was 3.6 months (range: 1.7-6.8 months) and 6.3 months at diagnosis (range: 2.5-9.3 months). All but 1 patient died at a median age of 8.2 months (range: 4.7-18.7 months). Molecular analysis revealed 20 different mutations, 6 of which are novel (c.1356delC, c.378G>A, c.1827C>G, c.859-2 A>T, c.1551+2T>G, and c.1465G>T). The most common mutation in the study was c.1935C>A, accounting for 25% (9/36 alleles) of the mutations. Our study provides the first comprehensive examination of the clinical course of infantile-onset Pompe disease and mutations of the GAA gene for patients in Mainland China. Our results confirm the high prevalence of the c.1935C>A mutation, previously reported for other populations, in Mainland Chinese patients with infantile-onset Pompe disease. Furthermore, six novel mutations in the GAA gene are reported for the first time.