Genome-wide Single Cell Haplotyping as a Generic Method for Preimplantation Genetic Diagnosis

Summary

The investigators previously developed approaches to SNP-, CNV- and haplo-type single human cells (Vanneste et al. 2009, Nature Medicine). These methods open the possibility to be developed into a novel generic diagnostic technique which broadens the spectrum of disease-alleles that can be selected against during preimplantation genetic diagnosis (PGD) and which enables to help those couples that cannot be supported by PGD yet. PGD is the genetic analysis of a single blastomere from an in vitro fertilized (IVF) embryo and it is offered to couples to avoid the transmission of heritable genetic disorders to their offspring. PGD analyses are performed for (1) autosomal dominant or recessive monogenic diseases, (2) X-linked disorders and (3) chromosomal aberrations that may result in aneuploid conceptions. This novel method is likely to outperform and hence, replace current techniques for preimplantation genetic diagnosis. In this project the investigators will bring the technology from a proof-of-principle to the clinical application. To this end the investigators will make computational improvements for accurate single blastomere SNP-, CNV- and haplo-typing and perform a large validation study. For the validation studythe investigators will analyse the genomes of the blastomeres derived from 60 spare embryos of different origin: (1) Embryos diagnosed as genetically abnormal using current PCR- and FISH-protocols. (2) Embryos diagnosed as normal for the investigated region using current PCR- and FISH-protocols, but not of sufficient quality to be transferred or frozen. (3) Embryos of the sex that is selected against following PGD based sex-selection, or embryos of the sex that is selected for but of insufficient quality to be transferred or frozen. (4) Embryos that were not biopsied in a PGD cycle since they suffer a slight growth delay. This validation study will allow us to evaluate (1) the clinical validity (false positive and negative rate) and (2) clinical applicability (in terms of ease of use, success rate, etc.). In addition, it will bring us essential further fundamental insights in the origins and mechanisms of chromosomal instability operating during early embryogenesis and its consequences for clinical applications of PGD. Finally, following the validation study, this project will clinically implement the technique to treat 10 families.

Conditions

• Preimplantation Genetic Diagnosis

Interventions

OTHER

single cell haplotyping

We aim to collect single blastomeres from spare IVF embryos of 30 couples to optimize and test methods for single cell haplotyping. We aim to collect 20 and 10 couples coming to the fertility centre for FISH- or PCR-based PGD respectively. In both groups, at least 5 different indications for PGD will be collected. Per couple, we will perform 10 SNP-arrays: 2 for the couple donating the embryo, 4 for family members (often parents of the couple) and 4 for blastomeres since we aim to pick 2 cells from 2 embryos per couple. For five couples, 2 blastomeres of all available embryos will be aspirated to validate and optimize the phasing methods. Finally, for some embryos, all blastomeres will be picked to be able to prove the reproducibility of single cell haplotyping.

Sponsors & Collaborators

• KU Leuven

  collaborator OTHER

• Universitair Ziekenhuis Brussel

  collaborator OTHER

• Vrije Universiteit Brussel

  collaborator OTHER

• Universitaire Ziekenhuizen KU Leuven

  lead OTHER

Principal Investigators

• Joris R Vermeesch, Professor · Universitaire Ziekenhuizen KU Leuven

• Thierry Voet, Professor · KU Leuven

• Thomas D'Hooghe, Professor · Universitaire Ziekenhuizen KU Leuven

• Yves Moreau, Professor · KU Leuven

• Karen Sermon, Professor · Vrije Universiteit Brussel

• De Rycke Martine, Professor · Universitair Ziekenhuis Brussel

Eligibility

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2010-10-31

Primary Completion

2013-09-30

Completion

2013-09-30

Countries

• Belgium

Study Locations