COL7A1 Gene Diagnosis And Prenatal Diagnosis Of Dominant Dystrophic Epidermolysis Bullosa In A Chinese Family

Purpose:To perform a DNA-based genetic diagnosis and prenatal diagnosis in a Chinese family with a moderately severe form of autosomal dominant dystrophic epidermolysis bullosa (DDEB).Method:COL7A1 gene mutations were detected by polymerase chain reaction and direct sequencing in 2 patients with different phenotype of DDEB, compared with 2 healthy family members and 50 unrelated healthy individuals. Prenatal genetic analysis and DNA prenatal diagnosis of fetal chorionic villi were performed in 2 high-risk fetuses of the family after the pathogenic mutation were determined.Results:Direct sequencing revealed that the proband and his mother carried the same heterozygous substitution mutation c.6859G>A p.Gly2287Arg in the 87th exon of COL7A1 gene. The mutation were not found in the 2 healthy family members as well as 50 healthy controls. The older sister of proband weren’t demonstrated as a carrier of the pathogenic mutation at 4 weeks of gestation. Her pregnancy continued and a healthy boy was born at gestation week 40. Prenatal diagnosis of fetal chorionic villi for the proband’s wife at 11 weeks of gestation were displayed the same mutation of the patient. The couples chose premature termination of pregnancy. The genetic diagnosis of fetal skin showed the same results of prenatal diagnosis.Conclusion:Glycine substitution mutations c.6859G>A, p.Gly2287Arg) is the causative mutation of this pedigree with different phenotype of DDEB. COL7A1 gene diagnosis and prenatal diagnosis can be quickly and accurately performed for DDEB. This study verify the feasibility of prenatal gene diagnosis in DDEB, which is conducive to birth of healthy offspring.