Table 1.
Primary causes of hypertriglyceridaemia
| A. Severe HTG (TG >10 mmol/L) | |
| Monogenic chylomicronaemia (formerly HLP Type 1 or familial chylomicronaemia syndrome) | |
| Lipoprotein lipase deficiency (Bi-allelic LPL gene mutations) | |
| Apo C-II deficiency (Bi-allelic APOC2 gene mutations) | |
| Apo A-V deficiency (Bi-allelic APOA5 gene mutations) | |
| Lipase maturation factor 1 deficiency (Bi-allelic LMF1 gene mutations) | |
| GPIHBP1 deficiency (Bi-allelic GPIHBP1 gene mutations) | |
| Multifactorial or polygenic chylomicronaemia (formerly HLP Type 5 or mixed hyperlipidaemia) | |
| Complex genetic susceptibility, including | |
| Heterozygous rare large-effect gene variants for monogenic chylomicronaemia (see above); and/or | |
| Accumulated common small-effect TG-raising polymorphisms (e.g. numerous GWAS loci including APOA1-C3-A4-A5; TRIB1, LPL, MLXIPL, GCKR, FADS1-2-3, NCAN, APOB, PLTP, ANGPTL3) | |
| Other | |
| Transient infantile HTG (glycerol-3-phosphate dehydrogenase 1 deficiency) from bi-allelic GPD1 gene mutations | |
| B. Mild-to-moderate HTG (TG 2.0–9.9 mmol/L) | |
| Multifactorial or polygenic HTG (formerly HLP Type 4 or familial HTG) | |
| Complex genetic susceptibility (see above) | |
| Dysbetalipoproteinaemia (formerly HLP Type 3 or dysbetalipoproteinaemia) | |
| Complex genetic susceptibility (see above), plus | |
| APOE E2/E2 homozygosity or | |
| APOE dominant rare variant heterozygosity | |
| Combined hyperlipoproteinaemia (formerly HLP Type 2B or familial combined hyperlipidaemia) | |
| Complex genetic susceptibility (see above), plus | |
| Accumulation of common small effect LDL-C-raising polymorphisms | |