Definition - What does Cytoplasmic Transfer mean?
Cytoplasmic transfer is an emerging technique in which cytoplasm from a donor egg is injected into the recipient egg, which has compromised mitochondria (the energy-producing units of the cell). The injected egg is then fertilized with the sperm and transferred to a uterus. The cytoplasm from an external source increase the quality of the egg and makes it viable.
Cytoplasmic transfer is also known as ooplasmic transfer.
FertilitySmarts explains Cytoplasmic Transfer
The first human pregnancy following cytoplasmic transfer was announced in the late 90s, after which this technique has successfully been used in a few women who have had recurrent implant failure or had poor embryo development. However, cytoplasmic transfer is currently banned in the U.S due to possible health and hereditary effects of ooplasmic transfer.
There are two types of cytoplasmic transfer.
- Synchronous transfer
- Asynchronous transfer
In synchronous transfer, the cytoplasm of the donor is transferred when both eggs are on the same developmental stage, whereas asynchronous transfer of cytoplasm is done between two eggs that are at different stages of development.
A child born from a cytoplasmic transfer has been referred to as a three-parent baby because he gets the genetic material from two mothers (donor mother’s mitochondrial DNA and genetic material from mother’s egg and father’s sperm).
Cytoplasmic transfer is often described as human germline modification or inheritable genetic modification (IGM). However, cytoplasmic transfer is not a form of IGM as it does not modify the genes present in the cell’s nucleus. IGM, on the other hand, makes deliberate changes in human genes to be passed on to children and future generations.