这个基因编码的蛋白质是乳糜微粒的一个主要的凋亡蛋白。它与特定的肝脏和外周细胞受体结合，对富含甘油三酯的脂蛋白成分的正常分解代谢至关重要。该基因与载脂蛋白C1和C2基因簇中的19号染色体定位该基因突变导致家族性β-脂蛋白血症或Ⅲ型高脂蛋白血症（HLP-Ⅲ），其中血浆胆固醇和甘油三酯升高是乳糜微粒和极低密度脂蛋白残留清除受损的结果。[由RefSeq提供，2016年6月]
The protein encoded by this gene is a major apoprotein of the chylomicron. It binds to a specific liver and peripheral cell receptor, and is essential for the normal catabolism of triglyceride-rich lipoprotein constituents. This gene maps to chromosome 19 in a cluster with the related apolipoprotein C1 and C2 genes. Mutations in this gene result in familial dysbetalipoproteinemia, or type III hyperlipoproteinemia (HLP III), in which increased plasma cholesterol and triglycerides are the consequence of impaired clearance of chylomicron and VLDL remnants. [provided by RefSeq, Jun 2016]