Resequencing genomic DNA of patients with severe hypertriglyceridemia (MIM 144650).
OBJECTIVE
The genetic determinants of severe hypertriglyceridemia (HTG; MIM 144650) in adults are poorly defined. We therefore resequenced 3 candidate genes, namely LPL, APOC2, and APOA5, to search for accumulation of missense mutations in patients with severe HTG compared with normolipidemic subjects.


RESULTS
We resequenced >2 million base pairs of genomic DNA from 110 nondiabetic patients with severe HTG and determined the prevalence of coding sequence variants compared with 472 age- and sex-matched normolipidemic controls. We found: (1) heterozygous mutations (LPL p.Q-12E >11X, p.D25H, p.W86R, p.G188E, p.I194T and p.P207L; APOC2 p.K19T and IVS2-30G>A) in 10.0% of severe HTG patients compared with 0.2% of controls (carrier odds ratio [OR] 52, 95% confidence interval [CI] 8.6 to 319); and (2) an association of the APOA5 p.S19W missense variant with severe HTG (carrier OR 5.5 95% CI 3.3 to 9.1). Furthermore, either rare mutations or the APOA5 p.S19W variant were found in 41.8% of HTG subjects compared with 8.9% of controls (carrier OR 7.4, 95% CI 4.5 to 12.0). Also, heterozygotes for rare mutations had a significantly reduced plasma triglyceride response to fibrate monotherapy.


CONCLUSIONS
Both common and rare DNA variants in candidate genes were found in a substantial proportion of severe HTG patients. The findings underscore the value of candidate gene resequencing to understand the genetic contribution in complex lipoprotein and metabolic disorders.
Wang
Jian
J
Vascular Biology Research Group, Robarts Research Institute and Schulich School of Medicine and Dentistry, London, Ontario, Canada.
Cao
Henian
H
Ban
Matthew R
MR
Kennedy
Brooke A
BA
Zhu
Siqi
S
Anand
Sonia
S
Yusuf
Salim
S
Pollex
Rebecca L
RL
Hegele
Robert A
RA
D000328:Adult; D000072040:Apolipoprotein A-V; D053304:Apolipoprotein C-II / Q000235:genetics*; D001054:Apolipoproteins A / Q000235:genetics*; D016022:Case-Control Studies; D002995:Clofibric Acid / Q000494:pharmacology; D005260:Female; D005787:Gene Frequency; D006801:Humans; D006953:Hyperlipoproteinemia Type IV / Q000188:drug therapy / Q000235:genetics*; D000960:Hypolipidemic Agents / Q000494:pharmacology; D008071:Lipoprotein Lipase / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense; D020641:Polymorphism, Single Nucleotide / Q000235:genetics; D044465:White People
C437704:APOA5 protein, human; D000072040:Apolipoprotein A-V; D053304:Apolipoprotein C-II; D001054:Apolipoproteins A; D000960:Hypolipidemic Agents; D002995:Clofibric Acid; D008071:Lipoprotein Lipase