Preimplantation Genetic Diagnosis for DEB by Detecting a Novel Family-Specific COL7A1 Mutation in Vietnam

Sang Trieutien,1,* Tam Vu Van,2,3,* My Tran Ngoc Thao,4 Son Trinh The,5 Khoa Tran Van,1 Tung Nguyen Thanh,5 Tuan Tran Van,5 Hanh Nguyen Thi6 1Department of Biology and Genetics, Vietnam Military Medical University, Hanoi, 12108, Vietnam; 2Director Office, Hai Phong Hospital of Obstetrics and Gynecology, Haiphong, 40000, Vietnam; 3Obstetrics and Gynecology Department, Haiphong University of Medicine and Pharmacy, Haiphong, 40000, Vietnam; 4Département de formation Biologie moléculaire et cellulaire, Sorbonne University, Paris, 75006, France; 5Military Institute of Clinical Embryology and Histology, Vietnam Military Medical University, Hanoi, 12108, Vietnam; 6Faculty of Biology, VNU University of Science, Vietnam National University, Hanoi, 12108, Vietnam*These authors contributed equally to this workCorrespondence: Son Trinh TheMilitary Institute of Clinical Embryology and Histology, Vietnam Military Medical University, Hanoi, 12108, VietnamEmail trinhthesonart@gmail.comBackground: Epidermolysis bullosa (EB) is a disorder characterized by the appearance of blisters, erosions and wounds in response to minimal trauma. The disease manifests with noticeable symptoms ranging from mild to severe, classified into four major types: epidermolysis bullosa simplex (EBS), junctional epidermolysis bullosa (JEB), dystrophic epidermolysis bullosa (DEB) and Kindler syndrome. Preimplantation genetic diagnosis for the disease remains the only available option for families at risk for the recurrence of the disorder without having to terminate an ongoing pregnancy.Materials and Methods: A novel COL7A1 mutation was used to design primers for the polymerase chain reaction (PCR) to amplify the segment spanning the mutation in the family and their in-vitro fertilization (IVF) embryos. Then, the PCR products were sequenced with Sanger sequencing to detect the alteration in the allele, and some embryos would go through NGS-based preimplantation screening for chromosomal abnormalities.Results: The established protocol for EB detected mutant allele in 6/9 embryos (66.6%), while the remaining 3 embryos (33.4%) appeared to not carry any mutation. Only one among 3 embryos was recommended to be transferred into the mother’s uterus.Conclusion: The established preimplantation genetic diagnosis procedure is helpful to families affected by epidermolysis bullosa caused by COL7A1 mutations but wish to have healthy children.Keywords: epidermolysis bullosa, rare dystrophic epidermolysis bullosa, EB, RDEB, skin disorder, COL7A1 gene mutation, preimplantation genetic diagnosis, PGD