Summary
Screening embryos created by IVF for chromosomal or genetic disorders before implantation.
In depth
A few trophectoderm cells are biopsied from day 5 blastocysts for PGT-A (aneuploidy), PGT-M (single-gene disorders) or PGT-SR (structural rearrangements). Limitations: mosaicism and ethical debate over selection.
Embryos are biopsied at blastocyst stage and frozen during analysis. Sequencing detects chromosome number and specific variants. Mosaic embryos present decision challenges.
Example: PGT-M allows couples with Huntington's risk to avoid transmission.
Frequently asked questions
What is Preimplantation Genetic Testing?
Screening embryos created by IVF for chromosomal or genetic disorders before implantation.
Which area of biology covers Preimplantation Genetic Testing, and how advanced is it?
Preimplantation Genetic Testing is one of the 54 topics in Developmental Biology. It is rated Advanced, so it suits learners who want specialist depth. Related topics in this area include Embryonic Stem Cells, Blastula, Induced Pluripotent Stem Cells.
Can you give an example of Preimplantation Genetic Testing?
Families with cystic fibrosis can select unaffected embryos.
What should I learn before Preimplantation Genetic Testing?
Work through the Beginner topics in Developmental Biology first, such as Fertilisation, Zygote, Embryo, then return to Preimplantation Genetic Testing. Advanced topics assume the Intermediate vocabulary.
What topics are related to Preimplantation Genetic Testing?
The closest topics to Preimplantation Genetic Testing are Embryonic Stem Cells, Blastula, Induced Pluripotent Stem Cells, Somites. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Preimplantation Genetic Testing?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Preimplantation Genetic Testing. To practise the whole of Developmental Biology, use the Developmental Biology quiz.
How is Preimplantation Genetic Testing different from Embryonic Stem Cells?
Preimplantation Genetic Testing: Screening embryos created by IVF for chromosomal or genetic disorders before implantation. Embryonic Stem Cells: Pluripotent cells from the blastocyst inner cell mass that can be grown and directed in culture. Read both side by side and note what each one explains.
How should I study Preimplantation Genetic Testing step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Embryonic Stem Cells and explain the difference aloud. Finally, take the Developmental Biology quiz and come back to this page for any question you miss.