PGT-A (formerly PGS) is a genetic test performed on embryos to identify numerical chromosomal abnormalities (aneuploidy).
Our PGT-A uses Next-Generation Sequencing (NGS), which allows us to analyze all 24 chromosomes. Chromosomal abnormalities are detected prior to embryo transfer to enable informed decisions and increase pregnancy success.
Independent studies have compared PGT-A from Igenomix and other labs and the highlights include:
MitoScore is a mitochondrial biomarker developed by Igenomix, which gives us an indicator of the energy status of an embryo.
MitoScore allows us to select those embryos with the greatest probabilities for implantation that are more likely to result in a viable pregnancy through IVF/ PGT-A.*
*(Diez-Juan et al. 2015)
The clinical translation of this work is the integration of the mtDNA copy number (MitoScore) with the routine genetic analysis performed in the PGT-A process.
PGT-A does not test for:
Birth defects
Inherited single gene disorders, such as cystic fibrosis or Tay-Sachs disease
Multifactorial conditions, including autism
Adult-onset conditions such as diabetes or Alzheimer´s disease
Physical and mental traits, such as intelligence or athleticism
Microdeletions/microduplications
As with most tests, PGT-A has some limitations:
1. Accuracy is ~98%
2. PGT-A tests only the samples produced by embryo biopsy, not whole embryos
3. PGT-A does not detect structural abnormalities that do not involve gains or losses of genetic material. Additionally, the following cannot be detected:
Follow-up prenatal testing is recommended to confirm the results of PGT-A.
There is a chance of unforeseeable problems with transportation, such as weather and air travel issues, or other circumstances beyond the control of Igenomix that may delay the reporting of results.
In a small percentage of cases, genetic testing cannot be performed due to improper biopsy techniques, loss of biopsied cells, or poor DNA quality.
Rubio et al: In vitro fertilization with preimplantation genetic diagnosis for aneuploidies in advanced maternal age: a randomized, controlled study. Fertil Steril. 2017 May;107(5):1122-1129.
Yang Z, Liu J, Collins GS, Salem SA, Liu X, Lyle SS, et al. Selection of single blastocysts for fresh transfer via standard morphology assessment alone and with array CGH for good prognosis IVF patients: results from a randomized pilot study. Mol Cytogenet 2012 May 2; 5(1):24.
Coates A, Kung A, Mounts E, Hesla J, Bankowski B, Barbieri E, Ata B, Cohen J, Munné S. Optimal euploid embryo transfer strategy, fresh versus frozen, after Preimplantation Genetic Testing for Aneuploidies with next generation sequencing: a randomized controlled trial. Fertil Steril. 2017 Mar;107(3):723-730.e3.
Coates A, Bankowski BJ, Kung A, Griffin DK, Munne S. Differences in pregnancy outcomes in donor egg frozen embryo transfer (FET) cycles following Preimplantation Genetic Testing for Aneuploidies (PGT-A): a single center retrospective study. J Assist Reprod Genet. 2017 Jan;34(1):71-78.
Sanchez-Ribas et al., Transcriptomic behavior of genes associated with chromo some 21 aneuploidies in early embryo development. Fertility and Sterility, 2019; 111, 5:991-1001.
Goldwaser, Tamar et al. Cell-free DNA for the detection of fetal aneuploidy. Fertility and Sterility, 2018; 109, 2, 195 – 200.
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Levy et al., Prenatal diagnosis by chromosomal microarray analysis. Fertility and Sterility, 2017; 109, 2, 201–212.
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Ottolini C. et al., Scientific Reports. Tripolar mitosis and partitioning of the genome arrests human preimplantation development in vitro, 2017;7:9744.
Munné, Santiago et al. Mosaicism: “survival of the fittest” versus “no embryo left behind”. Fertility and Sterility, 2016; 105, 5, 1146 – 1149.
Bolton et al., Mouse model of chromosome mosaicism reveals lineage-specific depletion of aneuploid cells and normal developmental potential. Nature Communications, 2016; 29;7:11165.
Cimadomo D. et al, The Impact of Biopsy on Human Embryo Developmental Potential during Preimplantation Genetic Diagnosis. Hindawi, 2016, 7193075.
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McCoy RC, Demko ZP, Ryan A, Banjevic M, Hill M, Sigurjonsson S, et al. Evidence of Selection against Complex Mitotic-Origin Aneuploidy during Preimplantation Development. PLoS Genet, 2015; 11 (10): e1005601.
Kung A. et al., Validation of next-generation sequencing for comprehensive chromosome screening of embryos. Reproductive BioMedicine, 2015; 1472-6483.
Greco E, Minasi MG, Fiorentino F. Healthy Babies after Intrauterine Transfer of Mosaic Aneuploid Blastocysts, N Engl J Med, 2015; Nov 19;373(21):2089-90.
Yang Z et al., Selection of single blastocysts for fresh transfer via standard morphology assessment alone and with array CGH for good prognosis IVF patients: results from a randomized pilot study., 2012, 5:24.
Sex selection and Sex determination, before and after conception is prohibited and punishable under PC & PNDT act no. 57 of 1994
