Preimplantation diagnosis for Fanconi anemia combined with HLA matching.

CONTEXT: The advent of single-cell polymerase chain reaction (PCR) has presented the opportunity for combined preimplantation genetic diagnosis (PGD) and HLA antigen testing. This is a novel and useful way to preselect a potential donor for an affected sibling requiring stem cell transplantation.

OBJECTIVE: To perform in vitro fertilization (IVF) and preimplantation HLA matching combined with PGD for Fanconi anemia (FA).

DESIGN: DNA analysis for the IVS 4 + 4 A-->T (adenine to thymine) mutation in the FA complement C (FANCC) gene in single blastomeres, obtained by biopsy of embryos, to identify genetic status and HLA markers of each embryo before intrauterine transfer.

SETTING: In vitro fertilization programs at large medical centers in Chicago, Ill, and Denver, Colo.

PARTICIPANTS: A couple, both carriers of the IVS 4 + 4 A-->T mutation in the FANCC gene with an affected child requiring an HLA-compatible donor for cord blood transplantation.

MAIN OUTCOME MEASURES: DNA analysis of single blastomeres to preselect unaffected embryos representing an HLA match for the affected sibling.

RESULTS: Of 30 embryos tested in 4 IVF attempts, 6 were homozygous affected and 24 were unaffected. Five of these embryos were also found to be HLA-compatible, of which 2 were transferred in the first and 1 in each of the other 3 cycles, resulting in a pregnancy and birth of an unaffected child in the last cycle.

CONCLUSION: To our knowledge, this is the first PGD with HLA matching, demonstrating feasibility of preselecting unaffected embryos that can also be an HLA-compatible source for stem cell transplantation for a sibling.