Clinical aspects of preimplantation genetic diagnosis for single gene disorders combined with HLA typing.

Preimplantation genetic diagnosis (PGD) for single gene disorders combined with human leukocyte antigen (HLA) matching has recently emerged as a therapeutic tool for stem cell transplantation in couples bearing an affected offspring. There may exist, however, several patient- or cycle-specific limitations for certain couples. This article documents data regarding experience of single gene disorders combined with HLA matching obtained at Istanbul Memorial Hospital, Turkey. The data were obtained from 20 couples undergoing 26 PGD-HLA cycles for thalassaemia (n = 23), Wiscott-Aldrich syndrome (n = 1) and acute lymphoblastic leukaemia (n = 2). A total of 206 embryos was biopsied on day 3 of embryo development and subsequently analysed. After the analysis, 26 (12.6%) of them were found to be both healthy and HLA compatible. In 16 embryo transfers performed, seven (43.7%) clinical pregnancies were obtained, one of which resulted in miscarriage. Ten of the 26 cycles started (38.4%) were cancelled due to a lack of suitable (mutation-free and/or HLA-compatible) embryos. The data suggest that application of PGD in combination with HLA typing is a promising therapeutic tool for an affected sibling.