G
Genetic Archaeology
GENETIC ARCHAEOLOGY // PROFILE

PEMT

Phosphatidylethanolamine N-Methyltransferase

CHR 17
17p11.2

Overview

PEMT encodes an enzyme responsible for the endogenous synthesis of phosphatidylcholine (PC) from phosphatidylethanolamine, which is particularly important for choline metabolism.

📍 Chromosomal Position

17p11.2 (Chromosome 17)

🧬 Gene Category

Vitamins

🔬 Inheritance

Codominant

📊 Prevalence

~40% carry the T allele

Function & Significance

PEMT catalyzes the methylation of phosphatidylethanolamine to phosphatidylcholine in the liver. This is the only pathway for endogenous PC synthesis without dietary choline.

🤰 Particularly Important for Women

PEMT is regulated by estrogen:

  • Women have higher PEMT activity than men
  • Variants increase choline requirements, especially in women
  • Critical during pregnancy and lactation
  • Fetal brain development requires significant amounts of choline

🧬 Relevant SNPs

Key PEMT variants:

rs12325817
17:17468645
Allele 1

C

/

Allele 2

T

Significance: Reduced PEMT activity, increased choline requirement (especially in women). T allele carriers have a higher risk of fatty liver if choline levels are low.

rs7946
17:17469003
Allele 1

C

/

Allele 2

T

Significance: Val175Met – influences PEMT enzyme activity and choline metabolism. The effect is amplified when combined with rs12325817.

🥚 Choline-Rich Foods

Recommended for PEMT variants:

  • Eggs: Best source (147 mg/egg)
  • Liver: Very high content
  • Fish: Salmon, cod
  • Cruciferous Vegetables: Broccoli, cauliflower
  • Legumes: Soybeans, chickpeas
  • Supplementation: 400-550 mg/day (during pregnancy)

📚 Data Sources

The information on this page is based on the following scientific sources:

  • OMIM: #605461 – Online Mendelian Inheritance in Man
  • dbSNP: rs12325817, rs7946 – SNP Database (NCBI)
  • ClinVar: Clinical Variant Database (NCBI)
  • PubMed: Choline Metabolism & Pregnancy Research
  • NIH: Phosphatidylcholine Synthesis Studies

Last Update: February 2026

Associated Risks

  • 🫀 Fatty Liver (NAFLD)

    Increased risk with low choline

  • 🤰 Neural Tube Defects

    Associated with choline deficiency during pregnancy

  • 💪 Muscle Damage

    In cases of severe choline deficiency

Biological Function

PEMT catalyzes the methylation of phosphatidylethanolamine to phosphatidylcholine in the liver. This is the only pathway for endogenous PC synthesis without dietary choline. Variants in PEMT increase the requirement for dietary choline, especially in women and during pregnancy.

Associated Conditions

Non-Alcoholic Fatty Liver Disease (NAFLD) Choline Deficiency Neural Tube Defects (with low choline) Muscle damage with choline deficiency
Molecular Analysis

Analyzed Markers

rs12325817 Risk Factor
Pos: 17:17468645 | Alleles: C/T

Reduced PEMT activity, increased choline requirement (especially in women)

rs7946 Modifier
Pos: 17:17469003 | Alleles: C/T

Val175Met - Influences PEMT enzyme activity and choline metabolism