Use of single nucleotide polymorphism microarrays to distinguish between balanced and normal chromosomes in embryos from a translocation carrier.

OBJECTIVE: To prove the ability to distinguish between balanced and normal chromosomes in embryos from a translocation carrier.
DESIGN: Case report.
SETTING: Academic center for reproductive medicine. PATIENT(S): Woman with a balanced translocation causing Alagille syndrome seeking preimplantation genetic diagnosis (PGD). INTERVENTION(S): Blastocyst biopsy for PGD. MAIN OUTCOME MEASURE(S): Consistency of 3 methods of embryo genetic analysis (real-time polymerase chain reaction, single nucleotide polymorphism [SNP] microarray, and fluorescence in situ hybridization [FISH]) and normalcy in the newborn derived from PGD. RESULT(S): PGD was applied to 48 embryos. Real-time polymerase chain reaction, SNP microarray, and FISH demonstrated 100% consistency, although FISH failed to detect aneuploidies observed by comprehensive SNP microarray-based analyses. Two blastocysts were identified to be normal for all 3 factors using SNP microarray technology alone. The 2 normal embryos were transferred back to the patient, resulting in the delivery of a healthy boy with a normal karyotype. CONCLUSION(S): This is the first report of validation and successful clinical application of microarray-based PGD to distinguish between balanced and normal chromosomes in embryos from a translocation carrier.