TY - JOUR
T1 - SNP array-based copy number and genotype analyses for preimplantation genetic diagnosis of human unbalanced translocations
AU - van Uum, Chris M. J.
AU - Stevens, Servi J. C.
AU - Dreesen, Joseph C. F. M.
AU - Drusedau, Marion
AU - Smeets, Hubert J.
AU - Hollanders-Crombach, Bertien
AU - de Die-Smulders, Christine E. M.
AU - Geraedts, Joep P. M.
AU - Engelen, John J. M.
AU - Coonen, Edith
PY - 2012/9
Y1 - 2012/9
N2 - Preimplantation genetic diagnosis (PGD) for chromosomal rearrangements (CR) is mainly based on fluorescence in situ hybridisation (FISH). Application of this technique is limited by the number of available fluorochromes, the extensive preclinical work-up and technical and interpretative artefacts. We aimed to develop a universal, off-the-shelf protocol for PGD by combining single-nucleotide polymorphism (SNP) array-derived copy number (CN) determination and genotyping for detection of unbalanced translocations in cleavage-stage embryos. A total of 36 cleavage-stage embryos that were diagnosed as unbalanced by initial PGD FISH analysis were dissociated (n=146) and amplified by multiple displacement amplification (MDA). SNP CNs and genotypes were determined using SNP array. Epstein-Barr Virus-transformed cell lines with known CR were used for optimising the genomic smoothing (GS) length setting to increase signal to noise ratio. SNP CN analysis showed 23 embryos (64%) that were unbalanced in all blastomeres for the chromosomes involved in the translocation, 5 embryos (14%) that were normal or balanced in all blastomeres and 8 embryos (22%) that were mosaic. SNP genotyping, based on analysis of informative SNP loci with opposing homozygous parental genotypes, confirmed partial monosomies associated with inheritance of unbalanced translocation in surplus embryos. We have developed a universal MDA-SNP array technique for chromosome CN analysis in single blastomeres. SNP genotyping could confirm partial monosomies. This combination of techniques showed improved diagnostic specificity compared with FISH and may provide more reliable PGD analysis associated with higher embryo transfer rate. European Journal of Human Genetics (2012) 20, 938-944; doi:10.1038/ejhg.2012.27; published online 29 February 2012
AB - Preimplantation genetic diagnosis (PGD) for chromosomal rearrangements (CR) is mainly based on fluorescence in situ hybridisation (FISH). Application of this technique is limited by the number of available fluorochromes, the extensive preclinical work-up and technical and interpretative artefacts. We aimed to develop a universal, off-the-shelf protocol for PGD by combining single-nucleotide polymorphism (SNP) array-derived copy number (CN) determination and genotyping for detection of unbalanced translocations in cleavage-stage embryos. A total of 36 cleavage-stage embryos that were diagnosed as unbalanced by initial PGD FISH analysis were dissociated (n=146) and amplified by multiple displacement amplification (MDA). SNP CNs and genotypes were determined using SNP array. Epstein-Barr Virus-transformed cell lines with known CR were used for optimising the genomic smoothing (GS) length setting to increase signal to noise ratio. SNP CN analysis showed 23 embryos (64%) that were unbalanced in all blastomeres for the chromosomes involved in the translocation, 5 embryos (14%) that were normal or balanced in all blastomeres and 8 embryos (22%) that were mosaic. SNP genotyping, based on analysis of informative SNP loci with opposing homozygous parental genotypes, confirmed partial monosomies associated with inheritance of unbalanced translocation in surplus embryos. We have developed a universal MDA-SNP array technique for chromosome CN analysis in single blastomeres. SNP genotyping could confirm partial monosomies. This combination of techniques showed improved diagnostic specificity compared with FISH and may provide more reliable PGD analysis associated with higher embryo transfer rate. European Journal of Human Genetics (2012) 20, 938-944; doi:10.1038/ejhg.2012.27; published online 29 February 2012
KW - preimplantation genetic diagnosis
KW - SNP array
KW - chromosomal translocations
KW - whole-genome amplification
KW - genotyping
KW - blastomeres
U2 - 10.1038/ejhg.2012.27
DO - 10.1038/ejhg.2012.27
M3 - Article
C2 - 22378284
VL - 20
SP - 938
EP - 944
JO - European Journal of Human Genetics
JF - European Journal of Human Genetics
SN - 1018-4813
IS - 9
ER -