Karyomapping allows preimplantation genetic diagnosis of a de-novo deletion undetectable using conventional PGD technology.
Preimplantation genetic diagnosis (PGD) was carried out for a couple carrying a de-novo deletion in the TSC2 gene, responsible for tuberous sclerosis. Karyomapping, a method employing genome-wide analysis of single nucleotide polymorphisms (SNP), was used as PGD protocol. Analysis of DNA from the affected parent using karyomapping confirmed the region covered by the deletion and revealed more than 30 SNP located within the affected region. These SNP were subsequently used for embryo diagnosis (deletion revealed by hemizygosity and/or reduced probe intensity). Seven blastocyst embryos underwent trophectoderm biopsy followed by vitrification. Biopsied cells were subjected to comprehensive aneuploidy screening using microarray comparative genomic hybridization (aCGH), with karyomapping for the detection of embryos carrying the mutant TSC2 gene carried out in tandem. Two embryo transfers were performed, the second of which resulted in the birth of a child. This study highlights that karyomapping may be applicable to a subset of de-novo mutations undetectable using standard PGD strategies. Additionally, karyomapping results were in complete concordance with aCGH, both methods revealing the same aneuploidies in the embryos tested. It was concluded that karyomapping may represent a valuable advance in cases of PGD for monogenic diseases.
Reprogenetics Spain, S.A., C/Tuset, 23, 6è1a, 08006 Barcelona, Catalonia, Spain. Electronic address: litus@reprogenetics.es.
Carles
C
Giménez
Reprogenetics UK, Institute of Reproductive Sciences, Oxford Business Park North, Oxford OX4 2HW, UK.
Jonás
J
Sarasa
Reprogenetics Spain, S.A., C/Tuset, 23, 6è1a, 08006 Barcelona, Catalonia, Spain.
César
C
Arjona
Instituto de Reproducción CEFER Lleida, C/Governador Montcada, 13, 25002 Lleida, Catalonia, Spain.
Ester
E
Vilamajó
Laboratori de Seminologia i Embriologia, Fundació Puigvert, C/Cartagena 340, 08025 Barcelona, Catalonia, Spain.
Olga
O
Martínez-Pasarell
Reprogenetics UK, Institute of Reproductive Sciences, Oxford Business Park North, Oxford OX4 2HW, UK.
Kenny
K
Wheeler
Instituto de Reproducción CEFER Lleida, C/Governador Montcada, 13, 25002 Lleida, Catalonia, Spain.
Gemma
G
Valls
Reprogenetics Spain, S.A., C/Tuset, 23, 6è1a, 08006 Barcelona, Catalonia, Spain.
Elena
E
Garcia-Guixé
Reprogenetics UK, Institute of Reproductive Sciences, Oxford Business Park North, Oxford OX4 2HW, UK.
Dagan
D
Wells
D000328:Adult; D002874:Chromosome Mapping / Q000379:methods*; D055028:Comparative Genomic Hybridization; D004624:Embryo Transfer; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007621:Karyotyping / Q000379:methods*; D008297:Male; D016133:Polymerase Chain Reaction / Q000379:methods; D020641:Polymorphism, Single Nucleotide; D011247:Pregnancy; D019836:Preimplantation Diagnosis / Q000379:methods*; D017384:Sequence Deletion; D020554:Sperm Injections, Intracytoplasmic
karyomapping; preimplantation genetic diagnosis; single gene diseases; single nucleotide polymorphism; tuberous sclerosis; whole genome amplification