Clinical results on single cells from 470 embryos using 23-chromosome single nucleotide polymorphism (SNP) microarray preimplantation genetic screening (PGS) from 45 patients

Abstract

OBJECTIVE: We amplified DNA from a single blastomere or trophectoderm cells and performed complex SNP microarray genetic analyses. DESIGN: Prospective study. MATERIALS AND METHODS: PGS patients between 12/1/09 and 4/25/10 were analyzed. 45 patients underwent embryo biopsy by laser and SNP microarray PGS primarily due to > 2 spontaneous miscarriages. 3 of these patients were tested for translocation abnormalities and aneuploidy. The maternal ages ranged from 34 to 44yrs. 398 embryos from 37 patients underwent day-3 biopsies, whereas 72 embryos from 8 patients underwent blastocyst trophectoderm biopsies. We amplified the DNA using a modified whole genome amplification (WGA) protocol. We used the Illumina Cyto-12 microarray to determine chromosome aberrations and to obtain genotype data for ∼300K SNPs. A high-resolution copy-number profile was used to identify copy number variations (CNVs). Parental DNA was simultaneously analyzed with embryo DNA for CNVs. Data was analyzed with Illumina GenomeStudio software. RESULTS: 45 patients and 470 embryos were tested. 37 patients undergoing a day-3 biopsy were considered for embryo transfer along with 1 patient undergoing a blastocyst biopsy. All embryos from an additional 7 patients undergoing blastocyst biopsies and PGS were frozen. 59% (277/470) of the embryos were abnormal. Many embryos with CNVs were considered normal because of parental CNV analysis. 3.1 ± 2 euploid embryos were identified per patient/cycle. The overall clinical pregnancy rate was 62%. The blastocyst biopsy transferred patient is pregnant.Tabled 1Clinical Pregnancy by Age GroupAgeClinical PregnancyMiscarriageNo TransferFrozen〈3556% (5/9)4% (1/23)0235-3763% (5/8)01038-4075% (9/12)004〉4044% (4/9)041 Open table in a new tab CONCLUSION: 23-chromosome SNP microarray PGS is a valuable technology in an effort to optimize the transfer of euploid embryos and to increase the delivery rates of couples undergoing in vitro fertilization (IVF) due to repeat miscarriages.