ZNF259/APOA5 — The Triglyceride Control Locus
At chromosome 11q23.3 sits a tightly packed cluster of lipid-metabolism
genes — APOA5, APOA4, APOC3, and APOA1 — flanked by ZNF259 (also known
as ZPR1) and BUD13. The rs964184 variant lies in the 3' untranslated
region of ZNF259, but its most important effect is on the neighboring
APOA5 gene, which encodes apolipoprotein AV | ApoAV is a secreted protein
produced mainly in the liver that activates lipoprotein lipase, the enzyme
that breaks down triglyceride-rich particles in the bloodstream. G allele
carriers produce less ApoAV protein after meals, impairing the clearance of
triglyceride-carrying particles from circulation.
The Mechanism
rs964184 is a 3'UTR regulatory variant in ZNF259. Although its precise
molecular mechanism is not fully resolved, functional studies have
established a direct link between rs964184 genotype and postprandial ApoAV
protein levels | Weissglas-Volkov et al. Genomic study in Mexicans identifies
a new locus for triglycerides and refines European lipid loci. J Med Genet,
2013. The G allele reduces ApoAV
availability, which in turn impairs lipoprotein lipase activation — the rate-
limiting step in clearing very-low-density lipoprotein (VLDL) triglycerides
from the blood. This effect is dose-dependent: heterozygotes (CG) show
intermediate triglyceride levels, while G;G homozygotes show the highest
elevations.
The Evidence
rs964184 is one of the most replicated triglyceride-associated variants in
the human genome, with genome-wide significant associations across European,
East Asian, South Asian, African, and Latin American populations.
A large study of 5,547 patients with established vascular disease | van de
Woestijne et al. Rs964184 is related to elevated plasma triglyceride levels
but not to an increased risk for vascular events. PLoS One, 2014
found each G allele adds approximately 0.12 log-units to fasting triglycerides
(p=1.1×10⁻¹⁹), a substantial effect for a common variant. The G allele minor
allele frequency rose from 10.9% in patients with the lowest triglycerides
(<1 mmol/L) to 24.6% in those with the highest (4–10 mmol/L). Metabolic
syndrome prevalence was 52% in CC homozygotes vs 62% in GG homozygotes.
A cross-ethnic fine-mapping study | Weissglas-Volkov et al. Genomic study in
Mexicans identifies a new locus for triglycerides and refines European lipid
loci. J Med Genet, 2013 narrowed
the APOA5 locus signal to rs964184 as the single most likely causal variant
underlying both European and Mexican GWAS signals, and demonstrated its
functional link to postprandial ApoAV protein levels.
In an Iranian case-control study of metabolic syndrome, Mirhafez et al. |
Mirhafez et al. ZNF259 Gene Polymorphism rs964184 is Associated with Serum
Triglyceride Levels and Metabolic Syndrome. Int J Mol Cell Med, 2016
found CG+GG genotypes conferred OR 2.52 (95%CI 1.33–4.77, p=0.005) for
metabolic syndrome and elevated TG and LDL-C compared to wild-type CC.
A dietary intervention trial | Zhang et al. APOA5 genotype modulates 2-y
changes in lipid profile in response to weight-loss diet. Am J Clin Nutr, 2012
found that G allele carriers showed greater reductions in LDL cholesterol on
a long-term low-fat diet (20% fat), supporting genotype-specific dietary guidance.
Practical Actions
The key lever for G allele carriers is dietary fat composition and overall
caloric pattern. Saturated fat drives VLDL-TG production independently of
ApoAV, so reducing saturated fat intake directly lowers the TG burden that
the impaired clearance pathway must handle. Fish-derived omega-3s (EPA/DHA)
suppress hepatic TG synthesis via PPAR-alpha activation, providing a separate
route to lower fasting and postprandial TG. Fasting TG monitoring every 12
months helps track whether dietary changes are taking effect, since fasting TG
above 1.7 mmol/L (150 mg/dL) is a metabolic syndrome criterion and predicts
cardiovascular risk.
Interactions
rs964184 sits in the same linkage disequilibrium block as several other
triglyceride-associated variants at the APOA5 locus, including rs3135506
(APOA5 S19W missense) and rs662799 (APOA5 -1131T>C promoter). Carrying
risk alleles at multiple positions in this cluster produces additive
triglyceride elevation. The APOC3 variants rs2854116 and rs2854117 (also
on chromosome 11) affect the same triglyceride clearance pathway through
a different mechanism (ApoC-III-mediated inhibition of lipoprotein lipase)
— users carrying risk alleles at both rs964184 and APOC3 variants face
compounded impairment of TG clearance.
All Genotypes
Common genotype — normal triglyceride clearance through APOA5 pathway
You carry two copies of the common C allele at rs964184, the most frequent genotype at this locus. About 66% of people globally share this genotype (around 77% of Europeans). Your ZNF259/APOA5 pathway produces normal amounts of apolipoprotein AV after meals, supporting efficient clearance of triglyceride-rich particles from the bloodstream.
One G allele — mildly elevated triglyceride risk via reduced ApoAV
You carry one copy of the G allele at rs964184, a genotype found in approximately 30% of people globally (about 24% of Europeans). Your APOA5 pathway produces somewhat less apolipoprotein AV than CC carriers, modestly impairing postprandial triglyceride clearance. Each G allele adds approximately 0.12 log-units to fasting triglycerides on average — equivalent to roughly a 13% elevation in absolute TG concentration per allele. Metabolic syndrome risk is moderately elevated compared to CC.
Two G alleles — significantly elevated triglycerides; proactive dietary management needed
You carry two copies of the G allele at rs964184, a genotype found in approximately 3.5% of people globally (about 1.9% of Europeans, up to 6% in East Asian and Latino populations). GG homozygotes produce substantially less apolipoprotein AV than CC carriers, significantly impairing lipoprotein lipase activation and postprandial triglyceride clearance. Two G alleles roughly double the additive triglyceride elevation compared to one copy. Metabolic syndrome prevalence reaches approximately 62% in GG homozygotes versus 52% in CC homozygotes.