From the Lipid Research Group, Department of Vascular Medicine (M.E.W.,
P.W.A.R., L.F., J.C.D., M.P., J.J.P.K.), and the Department of Medical
Statistics (G.-J.T.), Academic Medical Centre, University of Amsterdam, the
Netherlands, and the Department of Medical Genetics, University of British
Columbia, Vancouver, Canada (S.N.P., M.R.H.).
Correspondence to Michael R. Hayden, Department of Medical Genetics, University of British Columbia, 416-2125 E Mall, Vancouver, BC V6T 1Z4, Canada. E-mail mrh{at}ulam.generes.ca
Methods and ResultsHere we report a significant alteration in
biochemical and clinical phenotype in subjects with familial
hypercholesterolemia (FH) who are heterozygous
for this N291S LPL mutation. Sixty-four FH heterozygotes carrying the
N291S mutation had significantly a higher TG level
(P=.004), a higher ratio of total
cholesterol to HDLC (P<.001), and lower
HDLC concentrations (P=.002) compared with 175 FH
heterozygotes without this LPL mutation. Moreover, the N291S mutation
conferred a significantly greater risk for developing
cardiovascular disease in FH heterozygotes compared
with FH heterozygotes without this LPL mutation (odds ratio, 3.875;
P=.006).
ConclusionsThese data provide evidence that a common LPL variant
(N291S) significantly influences the biochemical phenotype and
risk for cardiovascular disease in patients with FH.
Despite its association with dyslipoproteinemia, the association
between this common LPL mutation and premature CVD is still
controversial. We hypothesized that such an association might become
particularly apparent if this N291S mutation were studied in a
population at increased risk for premature
atherosclerosis. Animal models particularly susceptible
to atherosclerosis, such as mice with targeted
disruption of the apolipoprotein E gene or the gene for the LDL
receptor, have been effectively used to monitor the effects of changes
in other genes. For example, mice lacking functional LDL receptors
(LDLR -/-) have a predisposition to significant
hypercholesterolemia and premature
atherogenesis. When LDLR -/- mice are crossed with mice
overexpressing LPL, a significant attenuation of the biochemical and
clinical phenotype is observed.9
FH is a common autosomal dominant disorder of lipoprotein
metabolism, affecting
Recently, we reported that the N291S mutation in the LPL gene was
associated with reduced HDLC concentrations in FH
families,12 and it was suggested that LPL
mutations may underlie some cases of low HDL concentrations observed in
patients with FH.13 14 15 What remains unanswered,
however, is whether this common N291S LPL mutation influences
lipoprotein phenotype and risk for CVD in a large cohort of FH
patients. This study was therefore undertaken to assess whether this
common LPL mutation might be associated with a change in the risk for
CVD in patients with heterozygous FH.
Cases were defined as all FH heterozygotes who were positive for the
N291S mutation and who did not carry the common D9N mutation in the LPL
gene. From the remaining FH cohort who did not carry the N291S or the
D9N mutations in the LPL gene, a control group of 175 FH patients was
selected for comparison. These individuals were selected in a
case-control manner by selecting, from the cohort of 1045 available FH
heterozygotes, control subjects for each FH case matched for age, sex,
and body mass but blinded for all other parameters,
including lipid levels, blood pressure, smoking, alcohol intake, and
presence of CVD. Medical history, physical examination, lifestyle
habits, dietary assessments, and additional risk factors for CVD, as
well as laboratory analysis of lipid and lipoprotein levels and
routine biochemistry, were obtained in all cases and control
subjects.
DNA Analysis
Biochemical Analysis
Cardiovascular Disease
Statistical Analysis
All statistical analyses were performed by use of the Systat
statistical package (UBC) except the logistic regression models, which
were determined by use of the SPSS package (UBC). A value of
P<.05 was used to declare statistical significance.
Baseline Demographics, Anthropometry, and Risk Factor
Assessment
Lipoprotein Assessment
The total cohort of FH cases and control subjects was further
analyzed by sex. In women, a significantly lower HDLC
concentration (1.23±0.34 versus 1.44±0.35 mmol/L;
P=.003), higher TG concentration (1.67±1.04 versus
1.27±0.54 mmol/L; P=.007), and higher TC/HDL ratio
(8.00±2.98 versus 6.38±2.26, P=.001) was observed in FH
heterozygotes carrying the N291S mutation (n=34) compared with female
FH heterozygotes without this mutation (n=91).
A similar trend was observed in men, in whom lower HDLC (1.07±0.38
versus 1.19±0.36 mmol/L; P=.1), higher TG
concentrations (2.01±1.10 versus 1.55±0.71 mmol/L,
P=.01), and higher TC/HDL ratios (9.34±4.57 versus
7.50±2.57, P=.008) were observed in male FH heterozygotes
who carried the N291S mutation (n=30) compared with male FH
heterozygotes without this LPL mutation (n=84).
Logistic regression models incorporating the covariates of smoking,
sex, age, alcohol, BMI, systolic blood pressure, and
diastolic blood pressure were used to test for associations
between the N291S LPL mutation and the low HDL/high TG
phenotype. As illustrated in Table 3
Frequency of the N291S Mutation by TG and HDL Tertiles
In addition, within the lowest HDL tertile, FH heterozygotes with the
N291S mutation were significantly enriched compared with FH
heterozygotes without this mutation. Of the 64 heterozygotes with the
N291S mutation, 33 (51.56%) were found in this tertile compared with
47 of the 175 FH heterozygotes without this mutation (26.86%)
(P=.005; Fig 1A
Dividing the groups by TG tertiles revealed an
overrepresentation of FH heterozygotes with the N291S mutation
in the upper tertile. Of 81 subjects in this tertile, 29 (35.8%) were
N291S carriers compared to the middle (where 20 of 79 subjects
[25.3%] were N291S carriers) and lower TG tertiles (where15 out of
79 subjects [19.0%] were N291S carriers; P=.03; Fig 1B
In addition, FH patients with the N291S mutation were
overrepresented in the highest TG tertile (29 out of 64 FH
cases, 45.31%) compared with FH control subjects without the N291S
mutation (51 of 175 FH controls, 29.71%; P=.04). A lower
frequency of FH patients with this LPL mutation (15 out of 64 FH cases,
18.99%) compared with FH control subjects (64 of 175 FH control
subjects, 36.57%) was observed in the lowest TG tertile
(P=.08; Fig 1B
Influence of BMI
In the upper BMI tertile, significantly higher TG levels were
observed in FH patients with the N291S mutation (2.14±1.33
mmol/L) compared with FH control subjects without this LPL mutation
(1.61±0.70 mmol/L; P=.01; Fig 2A
Prevalence of CVD
Although the prevalence of CVD was significantly higher in FH cases
with the N291S mutation, no significant difference in age of onset of
CVD between FH cases and FH control subjects was observed. FH patients
with the N291S mutation had a mean age of onset of CVD of 49.0±12.8
years compared with 44.9±8.8 years in FH control subjects
(P=.3; data not shown).
Furthermore, no difference in the type of CVD was observed between FH
subjects with and without the N291S mutation. Of the 19 FH
heterozygotes with the LPL mutation, 15 had coronary artery
disease, 2 had cerebrovascular disease, and 2 had
peripheral vascular disease. Of the 21 FH control subjects
(without the N291S mutation) with CVD, 15 had coronary artery
disease, 4 had cerebrovascular disease, and 2 had
peripheral vascular disease. In addition, no difference in
the number of coronary events was observed between FH subjects
with and without the N291S mutation (data not shown).
Logistic regression analysis revealed a significant influence
of the N291S mutation on the likelihood of developing CVD in the FH
cohort. After adjustment for known risk factors, including smoking,
sex, age, alcohol intake, BMI, and systolic and
diastolic blood pressures, this LPL mutation conferred a
significantly increased risk of developing CVD in patients with FH (OR,
3.89; P=.003; 95% CI, 1.59 to 9.51). The addition of HDLC,
TG, and LDLC to the model had very little effect on these results (OR,
3.88; P=.006; 95% CI, 1.47 to 10.22; Table 4
Here, we demonstrate that the N291S LPL mutation, detected in 6.5% of
1045 FH heterozygotes studied, not only had a significant deleterious
effect on lipoprotein phenotype but also significantly
increased cardiovascular risk in subjects with this LPL
mutation.
Individuals with heterozygous FH manifest with elevated TC and LDL
cholesterol concentrations and have a significantly
increased predisposition to premature CVD.10 It
has been reported, however, that significant variability does exist
with respect to the biochemical and clinical phenotype in
FH.24 25 Apart from the elevated LDL
cholesterol concentrations observed in FH, numerous studies
of FH heterozygotes have observed a trend toward low HDLC
concentrations.13 14 15 26 Low HDLC and high
TG concentrations also have been shown to correlate positively with
increased frequency of myocardial infarction in men with
FH.27 Recently, we reported in FH families that
mutations in the LPL gene can result in reduced HDLC concentrations in
individuals carrying mutations in both the LDL receptor and LPL
genes.12 Here, we confirm and extend these
findings by illustrating the effect of the common N291S mutation in a
large cohort of FH heterozygotes.
Double FH/LPL heterozygotes presented with significantly lower
HDLC, higher TG, and higher TC concentrations and higher TC/HDL ratios
compared with FH heterozygotes without the N291S LPL mutation. This
mutation predisposed to the combined low HDLC/high TG phenotype
as illustrated by logistic regression analysis. Furthermore, FH
heterozygotes with this LPL mutation were enriched in the lowest HDL
and highest TG tertiles in this FH cohort.
The influence of the N291S mutation on lipid levels was most apparent
when acting in concert with increased BMI. Significant differences in
TG and HDLC were apparent only between FH N291S carriers and FH control
subjects in the middle and upper tertiles of body mass. These data
support prior observations of a significant interaction between this
mutation and increased body mass.6 8 This finding
may have clinical and therapeutic implications and could provide
support specifically for encouraging weight loss, particularly in FH
heterozygotes who carry this LPL mutation.
The overall incidence of CVD in this study population was in
keeping with the reported expected incidence for FH heterozygotes of
this age.10 Of 239 FH heterozygotes, 40 (16.74%)
with a mean age of 38.7±15.8 years had evidence of CVD.
In addition to the effect of this mutation on lipoprotein
phenotype, we were able to demonstrate a significant positive
association between this N291S mutation on
cardiovascular risk in FH heterozygotes. Logistic
regression analysis determined that in this cohort, the effect
of the N291S mutation in increasing the risk for developing CVD was
greater than any other risk factors added to the model (including
smoking, age, sex, alcohol intake, BMI, and systolic and
diastolic blood pressures). The effect of the N291S
mutation on CVD risk also was in part independent of its effect on
lipid levels, as illustrated in Table 4
Clearly, other factors may also influence the lipoprotein
phenotype and risk for atherosclerosis in
patients with FH. Dietary differences may account for an altered
phenotype in FH, as we have recently illustrated by comparing
the phenotypes of Chinese FH heterozygotes with the same LDL
receptor mutations residing in either China or Canada (S.N. Pimstone,
X-M Sun, C. du Souich, J.J. Frohlich, M.R. Hayden, A.K. Soutar,
unpublished data, 1997). Furthermore, additional genetic factors, Lp(a)
concentrations, and the underlying LDL receptor mutation might also
influence the FH phenotype. Although we were not able to
directly assess all of these in this study, these factors are unlikely
to account for these results. Patients with many different functional
LDL receptor mutations were included in the FH cohorts with and without
the N291S mutations. Furthermore, there were no differences in apo E
genotype frequencies between the groups (data not shown).
Within the cohort of 19 N291S subjects with CVD, all apo E
genotypes apart from apo E2/E2 were represented.
Lp(a) concentrations were not available from this cohort, but data with
respect to both apo E genotype and Lp(a) concentrations factors
predictably altering coronary risk in FH have been
contradictory.26 28 29 30 31 Furthermore, dietary
differences are unlikely to have had a significant influence on
coronary risk in this population. All of these subjects were
reported to be following a low fat/low cholesterol diet
monitored by the lipid clinics at which they were being followed.
The influence of this common LPL mutation on CVD risk must, at least in
part, be explained by the effect of the N291S mutation on LPL function.
This mutation decreases LPL catalytic activity both in vivo and in
vitro,5 32 resulting in impaired catabolism of
chylomicrons and VLDL particles and in
hypertriglyceridemia.1
Resulting TG elevations in carriers of the N291S mutation contribute to
a reduction in LDL particle size.33 Small, dense
LDL in association with impaired postprandial TG clearance observed in
carriers of the N291S mutation34 may in part be
responsible for increasing atherogenic risk in FH heterozygotes who
carry this LPL defect.
Here, we report for the first time that a large cohort of FH
heterozygous subjects also carrying the N291S LPL mutation have
significantly lower HDL levels, higher TG levels, and higher ratios of
TC to HDL and are at increased risk for cardiovascular
disease compared with FH heterozygotes without this mutation. Because
the LPL mutation segregates independently of the mutation in the LDL
receptor gene, LPL mutations may account in part for the variability of
TG and HDL levels observed in FH patients and FH families and
furthermore may contribute to the variability in the clinical course
observed in heterozygous FH. These data illustrate that this common LPL
variant is an independent risk factor for atherosclerotic disease in
patients heterozygous for FH and suggest that this common LPL mutation
may influence risk for CVD in the general population.
Received May 30, 1997;
revision received October 13, 1997;
accepted October 29, 1997.
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© 1998 American Heart Association, Inc.
Clinical Investigation and Reports
A Common Mutation in the Lipoprotein Lipase Gene (N291S) Alters the Lipoprotein Phenotype and Risk for Cardiovascular Disease in Patients With Familial Hypercholesterolemia
![]()
Abstract
Top
Abstract
Introduction
Methods
Results
Discussion
References
BackgroundRecently, a mutation in
the lipoprotein lipase (LPL) gene (N291S) has been reported in 2% to
5% of individuals in western populations and is associated with
increased triglyceride (TG) and reduced HDL
cholesterol (HDLC) concentrations.
Key Words: genetics lipoproteins atherosclerosis
![]()
Introduction
Top
Abstract
Introduction
Methods
Results
Discussion
References
Lipoprotein lipase is
a multifunctional protein, playing a major role in the hydrolysis of
TG-rich lipoproteins.1 Over 60 mutations in the
LPL gene have been described that result in a functionally defective
catalytic protein and that occur with a frequency of
1 in 500
persons.2 Recently, a more common serine for
asparagine substitution at residue 291 (N291S) in exon 6 of the LPL
gene has been described3 that is observed with
high frequency, ranging from 2% to 5% in different
populations.4 5 This N291S mutation is associated
with partial reduction in LPL activity, both in vivo and in
vitro,5 and has been associated with reduced
levels of HDLC and elevated TGs in some
populations.4 5 6 7 8
1 in 500 people in the western
world.10 Defects in the gene coding for the LDL
receptor result in disturbed clearance of LDL cholesterol
because of impaired hepatic LDL receptor function. In subjects with
heterozygous FH, concentrations of plasma cholesterol are
generally increased two to three times, and cholesterol
accumulates in extrahepatic sites, resulting in the typical
characteristics of FH, including tendon xanthomata and premature
CVD.10 Untreated,
75% of men and 40% of
women with heterozygous FH will undergo a coronary event before
60 years of age.11
![]()
Methods
Top
Abstract
Introduction
Methods
Results
Discussion
References
Study Population
A total of 1045 patients with FH, all residing in the
Netherlands, were enrolled in this study. The diagnosis of heterozygous
FH was based on either the presence of a documented LDL receptor
mutation and/or the following criteria: LDL cholesterol
levels above the 95th percentile for sex and age, the presence of
typical tendon xanthomas in the patient or in a first-degree relative,
or a pediatric relative with an LDL cholesterol level above
the 95th percentile for sex and age. Secondary causes of
hypercholesterolemia, including renal and
hepatic disease, alcohol abuse, diabetes mellitus, and hypothyroidism,
were excluded in all subjects. In addition, all biochemical and
clinical parameters were assessed at presenting lipid
clinic visits with subjects off lipid-lowering medication for at least
3 months. No subjects were first-degree relatives.
Genomic DNA was extracted from leukocytes as previously
described.16 The LPL N291S mutation was assessed
in 1045 FH heterozygotes by polymerase chain reaction amplification by
use of a mismatch primer and followed by digestion with RSA
I as described previously.17 All cases and
control subjects were also analyzed for the D9N mutation in the
LPL gene by methods described previously.18
Subjects were excluded from the study if they carried the D9N LPL
mutation.
Total plasma cholesterol was determined by an
enzymatic colorimetric procedure by use of
cholesterolesterase.19 HDLC was
determined after precipitation of apo-Bcontaining
lipoproteins.20 TGs were quantified by an
enzymatic colorimetric procedure by use of lipase,
glycerokinase, and glycerol-3-phosphate
oxidase.21 LDL cholesterol was
calculated by use of the Friedewald formula, which is valid up to a TG
level of 8 mmol/L.22 23
CVD was considered to be present if subjects met one of the
following criteria: (1) if subjects had undergone a myocardial
infarction, proven by ECG abnormalities and enzyme changes; (2) if the
patient had suffered an ischemic stroke; (3) if a diagnosis of
clinically documented angina pectoris had been made; (4) if a history
of intermittent claudication was present; or (5) if an intervention
by either coronary bypass surgery or balloon angioplasty had
been performed.
FH heterozygotes with and without the N291S mutation were
compared. Results are reported by use of untransformed and unadjusted
variables. Because both groups were matched for age, sex, andBMI,
standard t tests were used to compare means of the
variables studied. TGs were log transformed before
analysis, but untransformed levels are reported.
2 analysis was used to compare the
frequency of cases and control subjects in TG, HDL, and BMI tertiles.
For comparison of the prevalence of CVD in both groups, the Fisher's
exact test was used. Logistic regression analysis was performed
to assess the impact of the N291S mutation on lipid abnormalities and
cardiovascular risk.
![]()
Results
Top
Abstract
Introduction
Methods
Results
Discussion
References
Frequency of the N291S Mutation
Of the 1045 FH heterozygotes screened, 68 subjects (32 men and 36
women; 6.5%) were carriers of the N291S LPL mutation. This frequency
is not significantly different from previous estimates for the
frequency of this mutation in the Dutch general
population.5 Four of these subjects who also
carried the common D9N LPL mutation were excluded from the case cohort
for lipid, lipoprotein, and cardiovascular
assessment.
Baseline characteristics of FH heterozygotes with and without the
N291S mutation are shown in Table 1
.
These groups were matched for age, BMI, and sex ratio. There also were
no significant differences in blood pressure, smoking, alcohol intake,
and plasma glucose levels. Of the 64 FH heterozygotes with the N291S
mutation, 22 (34.4%) had a defined LDL receptor mutation. Of 175 FH
heterozygote control subjects without the N291S mutation, 46 (26.3%)
had a defined LDL receptor mutation (data not shown).
View this table:
[in a new window]
Table 1. Baseline Characteristics of FH Patients With and
Without the LPL N291S Mutation
Both groups of patients were similarly characterized by elevated
total and LDL cholesterol concentrations as expected for
patients with FH (Table 2
). FH
heterozygotes with the LPL N291S mutation had more marked
dyslipoproteinemia, characterized by higher TG levels
(P=.004) and lower HDLC levels (P=.002) compared
with FH heterozygotes without the N291S mutation. In addition,
significantly higher TC concentrations (P=.02) and ratios of
TC to HDLC (P<.001) were observed in FH heterozygotes with
the N291S mutation compared with FH heterozygotes without this mutation
(Table 2
). No significant differences between the groups were observed
with respect to LDL cholesterol.
View this table:
[in a new window]
Table 2. Lipid Levels in FH Patients With and Without the LPL
N291S Mutation
, the N291S mutation was associated with
an increased likelihood for low HDLC (<0.91 mmol/L; P=.02)
and elevated TG (>2.82 mmol/L; P=.02). In addition,
the N291S mutation was associated with an increased odds for having
combined dyslipidemia (HDL<0.91 and TG >2.82
mmol/L), but this did not reach statistical significance, probably
because of the small sample size (n=6) with this phenotype
(P=.09).
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Table 3. OR for Association Between the N291S Mutation and
the Low HDL/High TG Phenotype
The FH cohort (cases and control subjects) was divided into
tertiles for both HDL and TG levels. FH heterozygotes carrying the
N291S mutation were significantly enriched in the lowest HDL tertile
compared with the number of FH heterozygotes in the middle and upper
HDL tertiles. Of the 80 FH heterozygotes in the lowest HDL tertile, 33
(41.25%) were carriers of the N291S mutation compared with 18 of 81
(22.22%) in the middle HDL tertile (P=.015) and 13 of 78
(16.67%) in the upper tertile (P=.001; Fig 1A
).

View larger version (22K):
[in a new window]
Figure 1. A, Frequency of FH heterozygotes with and without
the N291S mutation by HDL tertiles. A significant enrichment of N291S
carriers is evident in the lowest HDL tertile. B, Frequency of FH
heterozygotes with and without the N291S mutation by TG tertiles. A
significant enrichment of N291S carriers is evident in the highest TG
tertile.
). Furthermore, in the highest HDL tertile,
FH patients with the N291S mutation were underrepresented.
Only 13 of 64 FH cases (16.76%) clustered in this tertile compared
with 65 of 175 FH control subjects (37.14%; P=.02; Fig 1A
).
).
).
The FH cohort was divided into tertiles of BMI as follows: (1) BMI
<22.31 kg/m2 (n=79), (2) BMI between 22.31 and
24.61 kg/m2 (n=80), and (3) BMI >24.61
kg/m2 (n=80). Within each BMI tertile, mean TG
and HDLC were compared for both FH heterozygotes with and without the
N291S mutation (Fig 2A
and 2B
).

View larger version (27K):
[in a new window]
Figure 2. A, Mean plasma TG concentrations in FH
heterozygotes with and without the N291S mutation by BMI tertiles.
Higher TG concentrations were evident in N291S carriers at higher BMI
tertiles but were not evident at the lowest BMI tertile, suggesting a
significant interaction between this common LPL mutation and body mass.
B, Mean plasma HDL of FH heterozygotes with and without the N291S
mutation by BMI tertiles. Lower HDLC was evident in N291S carriers at
higher BMI tertiles but was not evident at the lowest BMI tertile,
suggesting a significant interaction between this common LPL mutation
and body mass.
). In addition, in
this BMI tertile, significantly lower HDLC levels were observed in FH
patients with the LPL mutation (1.08±0.32 mmol/L) compared with
FH control subjects (1.29±0.38 mmol/L; P=.02; Fig 2B
).
In the middle BMI tertile, subjects with FH and the N291S mutation also
had lower HDLC (1.12±0.29 mmol/L versus 1.37±0.41 mmol/L;
P=.02) and higher TG levels (2.02±0.91 versus
1.42±0.55 mmol/L; P=.009) compared with FH control
subjects. No significant difference between FH cases and control
subjects was observed in the lowest BMI tertile with respect to either
TG or HDLC concentration. These results suggest a significant
interaction between BMI and this LPL mutation, with the phenotypic
effects of this mutation clearly unmasked in patients with high
BMIs.
The prevalence of CVD was almost two times greater in FH
heterozygotes with the N291S mutation compared with FH heterozygotes
without this mutation. Of the 64 FH cases, 19 had a history of CVD
compared with 21 of 175 FH control subjects (P=.002; Table 4
).
View this table:
[in a new window]
Table 4. Prevalence of and OR for CVD in FH Patients With and
Without the N291S Mutation
). In this
model, the N291S LPL mutation was the most significant predictor of CVD
status, followed by age (OR, 1.11; P<.001; 95% CI, 1.06 to
1.17), sex (OR, 0.23; P=.009; 95% CI, 0.08 to 0.69), and
BMI (OR, 1.29; P=.02; 95% CI, 1.05 to 1.59; data not
shown).
![]()
Discussion
Top
Abstract
Introduction
Methods
Results
Discussion
References
We have studied a cohort of FH heterozygotes to assess the effect
of a common LPL mutation (N291S) on both lipoprotein phenotype
and risk for atherosclerosis. Despite its previously
reported association with dyslipoproteinemia, the association between
this mutation and an increased incidence of atherosclerotic vascular
disease remains controversial. To assess this possible association, we
have studied a group of individuals already at high risk for CVD to
determine whether this mutation altered the risk for developing
atherosclerosis in this cohort.
. This finding may be related in
part to the roles of LPL outside its lipolytic function. Altered
proteoglycan binding or lipid particle uptake at the level of the
vessel wall might account for this finding. We must also point out that
only a single fasting lipid determination, as was undertaken in this
study, may underestimate the long-term effect of this LPL mutation on
lipoprotein metabolism. Serial lipid measurements in N291S
carriers before they go on a lipid-lowering diet with subsequent weight
loss may reveal a stronger association between this mutation, lipid
levels, and CVD risk.
![]()
Selected Abbreviations and Acronyms
apo
=
apolipoprotein
BMI
=
body mass index
CI
=
confidence interval
CVD
=
cardiovascular disease
FH
=
familial hypercholesterolemia
HDLC
=
HDL cholesterol
Lp
=
lipoprotein
LPL
=
lipoprotein lipase
OR
=
odds ratio
TC
=
total cholesterol
TG
=
triglyceride
![]()
Acknowledgments
This work was supported in part by the MRC Canada and
the Heart and Stroke Foundation of British Columbia and the Yukon. Dr
Hayden is an established investigator at the BC Children's
Hospital.
![]()
References
Top
Abstract
Introduction
Methods
Results
Discussion
References
1.
Brunzell JD. Familial lipoprotein lipase
deficiency and other causes of chylomicronemia syndrome. In: Scriver
CR, Beaudet AC, Sly WS, Valle D, eds. The Metabolic
Basis of Inherited Disease. 7th ed. New York, NY: McGraw Hill Book
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serine mutation with body mass index determines elevated
plasma triacylglycerol concentrations: a study in
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survivors, and healthy adults. J Lipid Res. 1995;36:21042112.[Abstract]
Asn):
functional implications and prevalence in normal and
hyperlipidemic subjects. Arterioscler Thromb Vasc
Biol. 1995;15:468478.
Ser mutation in the lipoprotein lipase
gene in two Finnish pedigrees: effect of
hyperinsulinemia on the expression of
hypertriglyceridemia. J Lipid
Res. 1996;37:727738.[Abstract]
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