sdLDL-C positively correlated with ApoC3 (r = 0.7517) and inversely with CETP activity (r = -0.2682).<h4>Conclusion</h4>Long-standing type 1 diabetes with adequate glycemic control is associated with an atherogenic sdLDL profile despite near-normal conventional lipid levels. This evidence concerns the gene APOC3 and type 1 diabetes mellitus.