Three-Parent Babies… Or Are They?

Evangeline Walker


Considering the topic of 3-parent IVF, this paper aims to determine how much DNA, in terms of base pairs of nucleotides, is actually contributed by the notorious ‘third parent’. By considering how much DNA is contained in the nucleus and mitochondria of an average cell, the percentage contributed by each parent to the recipient child is found to be 0.27% from the third parent, and 49.9% from each of the two conventional parents. An alternative calculation is also presented, using only the coding DNA region, however this is rationalised to be a less appropriate model. 


Health; Biology; Genetics; IVF

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