Successful pregnancies after combined human leukocyte antigen direct genotyping and preimplantation genetic diagnosis utilizing multiple displacement amplification

Abstract

Objective: To devise a new and simple technique to help select normal embryos that are human leukocyte antigen (HLA) matched to their affected siblings for diseases, such as beta-thalassemia or sickle cell anemia, which are common in this part of the world.

Methods: This study was conducted between March 2008 and April 2011 at the preimplantation Genetic Diagnosis Laboratory, Saad Specialist Hospital, Al-Khobar, Kingdom of Saudi Arabia. Embryos were obtained after 7 in vitro fertilization preimplantation genetic diagnosis (IVF-PGD) cycles. Single cells were biopsied, and extracted DNA was amplified by the multiple displacement amplification (MDA) technique. Amplified DNA was then tested for mutations in the beta-globin gene, and directly HLA typed using a sequence specific primer technique.

Results: We report 7 families that underwent 7 PGD cycles with HLA typing and direct HLA loci-typing using an HLA conventional commercial kit. Two patients had PGD and HLA typing for class I and II, while the other 5 had class II. The PGD cycles resulted in 3 pregnancies out of 5 patients who had HLA matched and normal embryos. One family had a successful hematopoietic stem cell transplant.

Conclusion: This report demonstrates the first clinical application of PGD coupled with direct HLA loci-typing of DNA amplified by MDA from a single cell.