[P2-40] Ten novel mutations of the ERCC6, ERCC8 genes associated with Cockayne syndrome and prenatal diagnosis for three fetuses
[Purpose] To identify mutations in genes associated with Cockayne syndrome among Chinese patients. Prenatal diagnosis for three fetuses was performed. [Methods] The clinical data and peripheral blood cells were collected from 11 Chinese patients (6 boys and 5 girls) and their family members. Targeted next-generation sequencing was used to detect mutations in the known 4000 Mendelian-disorder-gene panel including ERCC6, ERCC8, UVSSA et al. Sanger sequencing was used to confirm the mutations detected in the patients and their family members. [Results] 11 probands with Cockayne syndrome came from 11 unrelated nonconsanguineous Chinese families. They were diagnosed at the age of 5 months to 15 years. Nine probands were admitted because of progressive growth failure, progressive microcephaly, and mental retardation; while two patients had Reye-like syndrome. Eight mutations were detected in ERCC6. Seven of them were novel. Six mutations were found in ERCC8. Three of them were novel. Exon 4 deletion of ERCC8 occured in three probands. One of the fetuses was affected by Cockayne syndrome. Two fetuses were none affected. [Conclusion] Ten novel mutations in the ERCC6 and ERCC8 were identified in a population of 11 Chinese patients with Cockayne syndrome. The mutation of exon 4 deletion in ERCC8 might be a founder mutation or hotspot mutation in Chinese patients. Prenatal diagnosis for three fetuses was successfully performed by gene analysis of amniocytes.