Preimplantation genetic diagnosis for the Kell genotype.

ABSTRACT

OBJECTIVE: To use preimplantation genetic diagnosis (PGD) to achieve a Kell 1 (K1) allele-free pregnancy in couples at risk for producing a child with hemolytic disease of the newborn (HDN) caused by maternofetal incompatibility in sensitized mothers. DESIGN: DNA analysis of biopsied blastomeres from cleavage-stage embryos in IVF-ET with the goal of identifying and transferring back to patients the K1 allele-free embryos. SETTING: IVF program at the Reproductive Genetics Institute, Chicago, Illinois, and IVF Michigan, Rochester Hills, Michigan. PATIENT(S) Two at-risk couples with a history of neonatal death caused by HDN due to K1/K2 genotype in a male partner. INTERVENTION(S) Biopsy of single blastomeres and testing for paternal K1 allele in each embryo after standard IVF. MAIN OUTCOME MEASURE(S) DNA analysis of blastomeres indicating whether corresponding embryos were K1 allele-free for the purpose of transferring only embryos without the K1 allele. RESULT(S) Of 36 embryos tested in five cycles from two couples, 18 were predicted to be K1 allele-free. Of these, 9 were transferred, resulting in a K1 allele-free twin pregnancy and the birth of two healthy children. CONCLUSION(S) PGD of the K1 genotype resulted in the birth of healthy twins confirmed to be free of the K1 allele. PGD in couples with a heterozygous K1/K2 male partner provides an option for avoiding HDN in sensitized mothers.