Wednesday, July 25, 2018

Genomic Prediction: A Hypothetical (Embryo Selection)

The new SSGAC EA3 paper in Nature Genetics contains the following figure.


Add Health (National Longitudinal Study of Adolescent to Adult Health) and HRS (Health in Retirement Study) are two longitudinal cohorts under study by social scientists. Horizontal axis is polygenic score (computed from DNA alone). It appears that individuals with top quintile polygenic scores are about 5 times more likely to complete college than bottom quintile individuals.  (IIUC, HRS cohort grew up in an earlier era when college attendance rates were lower; Add Health participants are younger.)

Consider the following hypothetical:
You are an IVF physician advising parents who have exactly 2 viable embryos, ready for implantation. The parents want to implant only one embryo. 
All genetic and morphological information about the embryos suggest that they are both viable, healthy, and free of elevated disease risk.

However, embryo A has polygenic score (as in figure above) in the lowest quintile (elevated risk of struggling in school) while embryo B has polygenic score in the highest quintile (less than average risk of struggling in school). We could sharpen the question by assuming, e.g., that embryo A has score in the bottom 1% while embryo B is in the top 1%.

You have no other statistical or medical information to differentiate between the two embryos.

What do you tell the parents? Do you inform them about the polygenic score difference between the embryos?
Note, in the very near future this question will no longer be hypothetical...

See Nativity 2050 and The Future is Here: Genomic Prediction in MIT Technology Review.

No comments:

Post a Comment