rs1044250 — ANGPTL4 T266M

ANGPTL4 T266M — The Triglyceride Brake Variant

Your fat-clearing machinery runs a little faster than average if you carry the M266 variant of ANGPTL4. This gene encodes angiopoietin-like protein 4¹¹ angiopoietin-like protein 4
ANGPTL4 is a secreted protein produced mainly in the liver and fat tissue that regulates how the body clears triglycerides from the bloodstream after meals, one of the body's key brakes on the enzyme that breaks down fat in circulation. Carriers of the T allele at rs1044250 have a partially released brake — their lipoprotein lipase activity is somewhat less suppressed, leading to more efficient clearance of triglycerides from the blood.

The Mechanism

ANGPTL4 inhibits lipoprotein lipase (LPL)²² lipoprotein lipase (LPL)
LPL is the enzyme attached to the inner wall of blood vessels that breaks down triglyceride-rich particles (VLDL and chylomicrons) into fatty acids that can enter tissues, the enzyme responsible for extracting fat from VLDL and chylomicrons circulating in the blood. The missense change p.Thr266Met alters the C-terminal fibrinogen-like domain of ANGPTL4. Functional studies suggest this substitution partially reduces the protein's ability to inhibit LPL, allowing more triglyceride hydrolysis to proceed. The result: carriers process dietary and fasting triglycerides somewhat more efficiently than those with the common CC genotype.

The Evidence

A large multi-cohort study by Talmud et al.³³ Talmud et al.
Talmud PJ et al. ANGPTL4 E40K and T266M: effects on plasma triglyceride and HDL levels, postprandial responses, and CHD risk. Arterioscler Thromb Vasc Biol, 2008 across 13,527 individuals found that T266M was associated with a 10.4% reduction in fasting triglycerides (P<0.004). Importantly, when carriers were analyzed after a high-fat meal, T266M showed a significant reduction in postprandial triglyceride area under the curve (P=0.009), suggesting the variant matters most in the context of dietary fat load.

The Look AHEAD clinical trial analysis by Smart-Halajko et al.⁴⁴ Smart-Halajko et al.
Smart-Halajko MC et al. ANGPTL4 variants E40K and T266M are associated with lower fasting triglyceride levels in Non-Hispanic White Americans from the Look AHEAD Clinical Trial. BMC Med Genet, 2011 in 2,601 participants with type 2 diabetes found that TT homozygotes had fasting triglycerides 0.24 mmol/L lower than CC homozygotes (p=0.002). Crucially, this association held even after removing the more potent E40K variant carriers from the analysis (p=0.002), confirming T266M as an independent lipid-modifying variant.

For broader ANGPTL4 biology, a landmark NEJM study⁵⁵ NEJM study
Stitziel NO et al. Coding Variation in ANGPTL4, LPL, and SVEP1 and the Risk of Coronary Disease. N Engl J Med, 2016 in 193,638 individuals showed that ANGPTL4 loss-of-function variants as a class reduce triglycerides by up to 35% and are associated with lower coronary artery disease risk, with E40K (the more potent variant in the same gene) showing OR 0.86 (P=4×10⁻⁸) for CAD protection. A 2024 phenome-wide analysis in 797,432 individuals Gagnon et al.⁶⁶ Gagnon et al.
Gagnon E et al. Impact of loss-of-function in angiopoietin-like 4 on the human phenome. Atherosclerosis, 2024 confirmed LPL as the primary mediator and found no increased disease risk across 1,589 tested conditions in ANGPTL4 loss-of-function carriers.

The evidence for T266M specifically is moderate: the triglyceride-lowering effect is replicated, but effect sizes are modest (0.24 mmol/L reduction) compared to the rarer E40K variant, and the CHD protection has not been independently established for T266M in a study powered to detect it.

Practical Actions

For CC genotype carriers (no T266M): triglyceride management relies on the standard levers — dietary fat composition and carbohydrate quality are the primary modifiers. Monitoring fasting triglycerides is especially worthwhile if other lipid risk factors are present.

For CT and TT carriers: the genetic background confers modest triglyceride-lowering benefit. This doesn't eliminate cardiovascular risk on its own, but it does mean fasting triglycerides tend to run lower. The postprandial benefit (lower triglyceride spike after fatty meals) is particularly relevant for TT homozygotes, who have the greatest LPL disinhibition.

Interactions

T266M (rs1044250) belongs to the same gene as E40K (rs116843064), the more studied and more potent ANGPTL4 variant. When both are present together, the combined LPL disinhibition would be expected to produce additive triglyceride lowering, though this combination is rare (~2% MAF for E40K). ANGPTL4 functionally connects to LPL variants (LPL S447X, rs328) and to APOC3 variants (rs5128), which also regulate triglyceride clearance through overlapping but distinct mechanisms.