A closer look at a particular recommendation:

Gene: PEMT ( phosphatidylethanolamine N-methyltransferase )

Function: Converts phosphatidylethanolamine to phosphatidylcholine by methylation in the liver.

Here is a diagram of choline metabolism:

Disrupted PEMT function can block the creation of phosphatidylcholine.

23andMe assesses 57 snps on the gene PEMT. Of these, the ones that have been researched to have an impact on choline metabolism are:

rs12325817 http://www.ncbi.nlm.nih.gov/pubmed/1...?dopt=Abstract
rs7946 http://www.ncbi.nlm.nih.gov/pubmed/19167960 (disputed)

PEMT is induced by estrogen, so postmenopausal women have an increased need for choline as their estrogen is low. http://www.ncbi.nlm.nih.gov/pubmed/20861172 In addition, the need is further increased by the rs12325817 polymorphism and ameliorated by choline supplementation. http://www.ncbi.nlm.nih.gov/pubmed/21059658/

The consequences from choline deficiency (and observed with these mutations) are fatty liver and multiple organ dysfunction.


The great news is that supplementation with choline or phosphatidylcholine bypasses this genetic issue.