Embryo biopsy and development: the known and the unknown

Preimplantation genetic diagnosis (PGD) has been introduced in clinical practice as a tool for selecting ‘healthy’ embryos before their transfer in utero. PGD protocols include biopsy of cleaving embryos (blastomere biopsy (BB)) or blastocysts (trophectoderm biopsy (TB)), followed by genetic analysis to select ‘healthy’ embryos for transfer in utero. Currently, TB is replacing the use of BB in the clinical practice. However, based on the European Society of Human Reproduction and Embryology Preimplantation Genetic Diagnosis Consortium reports, BB has been used in >87% of PGD cycles for more than 10 years. An exhaustive evaluation of embryo biopsy (both BB and TB) risks and safety is still missing. The few epidemiological studies available are quite controversial and/or are limited to normalcy at birth or early childhood. On the other hand, studies on animals have shown that BB can be a risk factor for impaired development, during both pre- and postnatal life, while little is known on TB. Thus, there is an urgent need of focused researches on BB, as it has contributed to give birth to children for more than 10 years, and on TB, as its application is significantly growing in clinical practice. In this context, the aim of this review is to provide a complete overview of the current knowledge on the short-, medium- and long-term effects of embryo biopsy in the mouse model.

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Embryo Biopsy for Preimplantation Genetic Diagnosis

Principles and Practice of Assisted Reproductive Technology (3 Volumes) ◽

10.5005/jp/books/12151_101 ◽

2014 ◽

pp. 1061-1061

Author(s):

Shailaja Saxena ◽

Prabhat Ranjan

Keyword(s):

Preimplantation Genetic Diagnosis ◽

Genetic Diagnosis ◽

Embryo Biopsy

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Accuracy of preimplantation genetic diagnosis in equine in vivo-recovered and in vitro-produced blastocysts

Reproduction Fertility and Development ◽

10.1071/rd14419 ◽

2016 ◽

Vol 28 (9) ◽

pp. 1382 ◽

Cited By ~ 7

Author(s):

Y. H. Choi ◽

M. C. T. Penedo ◽

P. Daftari ◽

I. C. Velez ◽

K. Hinrichs

Keyword(s):

Preimplantation Genetic Diagnosis ◽

Whole Genome Amplification ◽

Genetic Diagnosis ◽

Periodic Paralysis ◽

Drop Out ◽

Embryo Biopsy ◽

Experimental Conditions ◽

Polysaccharide Storage Myopathy

Preimplantation genetic diagnosis has great potential in the horse, but information on evaluation of equine embryo biopsy samples is limited. Blastocysts were biopsied using a Piezo drill and methods for whole-genome amplification (WGA) investigated. Results for 33 genetic loci were then compared between biopsy samples from in vitro-produced (IVP) and in vivo-recovered (VIV) blastocysts. Under the experimental conditions described, WGA using the Qiagen Repli-g Midi kit was more accurate than that using the Illustra Genomiphi V2 kit (98.2% vs 25.8%, respectively). Using WGA with the Qiagen kit, three biopsy samples were evaluated from each of eight IVP and 19 VIV blastocysts, some produced using semen from stallions carrying the genetic mutations associated with the diseases hereditary equine regional dermal asthenia (HERDA), hyperkalemic periodic paralysis (HYPP) or polysaccharide storage myopathy 1 (PSSM1). Three of 81 biopsy samples (3.7%) returned <50% accuracy. In the remaining 78 samples, overall accuracy was 99.3% (2556/2574 loci interrogated). Accuracy did not differ significantly between samples from IVP and VIV blastocysts. Allele drop-out in heterozygous loci was 1.6% (17/1035). Accuracy for sex determination was 100%; accuracy for heterozygosity for disease-causing mutations was 97.7% (43/44). In conclusion, Piezo-driven embryo biopsy with WGA has >95% overall accuracy in IVP and VIV embryos, and this technique is suitable for use in a clinical setting.

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