(Hypertension. 1999;33:927-932.)
© 1999 American Heart Association, Inc.
Scientific Contributions |
From the Hypertension Gene Laboratory, Department of Physiology and Institute for Biomedical Research, The University of Sydney (Australia).
Correspondence to Brian J. Morris, DSc, Hypertension Gene Laboratory, Department of Physiology and Institute for Biomedical Research, Bldg F13, The University of Sydney, NSW 2006, Australia. E-mail brianm{at}physiol.usyd.edu.au
| Abstract |
|---|
|
|
|---|
21 df=1.1, P=0.3). Allele
frequencies for the multiallelic marker were also similar in each group
(
2 7 df=9.8, P=0.2).
Furthermore, no genotypic differences in blood pressure were apparent.
In the sib-pair study, SPLINK APM, and MAPMAKERS/SIBS did not indicate
excess allele sharing. We also examined genotype as a
function of age. In the younger (< 60 years) hypertensives as well as
younger or older normotensives, genotype and allele
frequency of the biallelic marker was similar (0.12 to 0.14). However,
in hypertensives
60 years of age, frequency of the minor allele
was 0.28 (
2=7.4, P=0.006). Homozygotes
for this allele were rare. Frequency of heterozygotes was 0.19 for
normotensives but 0.39 for the older hypertensives
(
2=8.0, P=0.018) and was 0.40 for
hypertensive sibs
60 years of age with a diastolic
pressure
100 mm Hg. Furthermore, homozygotes for the major
allele were 7 years younger than heterozygotes (P=0.05
by ANOVA). In conclusion, the present study shows (1) no evidence
for a role of NOS2A in hypertension and (2) a genotypic
difference in frequency of a NOS2A promoter variant in
older hypertensives, seen in 2 different cohorts. A possible
interpretation of the latter observation is that NOS2A
genotype could affect longevity, at least in patients at high
risk by having moderate to severe hypertension.
Key Words: whites hypertension, essential nitric oxide synthase genetics, biochemical polymerase chain reaction linkage (genetics) survival
| Introduction |
|---|
|
|
|---|
37 kb and
contains 26 exons,3 exons 22 to 26 also being
represented as 4 partially duplicated sequences in humans
and great apes at this (NOS2B, -C) and other
(-E) loci.4 NOS2A, along with the neuronal (n) NOS and endothelial (e) NOS isoform genes, NOS1 and NOS3 (chromosomes 12q24.2-q24.31 and 7q35-q36), respectively, are involved in the generation of NO, a potent vasodilator. NOS2A is expressed in various tissues, including some relevant to the cardiovascular system,5 viz, cardiac and vascular smooth muscle, renal tubules, and afferent arteriole. There is, moreover, evidence that intrarenal expression of iNOS can regulate arterial pressure.6
Although NO is reduced in essential hypertension,7 which may contribute to vascular and cardiac hypertrophy,8 and NO markers correlate inversely with blood pressure,7 there is no evidence to date that iNOS has a pathogenic role. In the spontaneously hypertensive rat (SHR), however, although iNOS expression is similar in vascular smooth muscle cells of prehypertensive rats and Wistar-Kyoto controls,9 sustained NO production is lower in SHR, and NOS2 transcription differs between cells of each strain, leading to a suggestion that iNOS could be involved in the early rise in blood pressure.9 Others have found abnormal expression later in SHR hypertension.10 In Sabra DOCA salt-hypertensive rats, iNOS expression is reduced compared with their salt-resistant control strain, and greater NO generation could contribute to the salt resistance of the latter.11 Dahl salt-sensitive hypertensive rats may have a defect in NO synthesis, seen in vivo12 as well as in primary cultures of aortic smooth muscle cells, and a transversion, T2140C (Ser714Pro), has been noted in the iNOS gene of Dahl rats.13 Moreover, various rat strains show a hypertension linkage region in the vicinity of Nos2.14 15 16 17 18
Two polymorphisms have been described for NOS2A. Both concern variation in repeated sequences and each is located in the 5'-flanking DNA. One is in an AAAT/AAAAT repeat at 756 to 716 relative to the major transcription start site (+1)19 and involves an insertion or deletion of 1 repeat unit.20 The other, located 2.7 to 2.5 kb upstream, consists of 8 alleles of a CCTTTn pentanucleotide repeat with heterozygosity 0.80.21 Of possible relevance to a disease such as hypertension, strand slippage in such repeats provides a rapid evolutionary mechanism for response to environmental change, with 9 to 16 repeat units in humans but only 3 to 9 in chimpanzees.21 Similar sequences form a triplex structure in vivo, leading to S1 nuclease-sensitive sites that may affect gene regulation.22 Poly-Pur/Pyr elements also occur in the 5'-flanking DNA of the ß-globin23 and rat AT1a angiotensin receptor24 genes, and, as for NOS2A,21 correspond to DNase I hypersensitive sites in active chromatin. Moreover, variation in repeat number in the insulin promoter affects promoter activity and onset of insulin-dependent diabetes mellitus (IDDM).25
Using these polymorphisms of NOS2A as markers, we have conducted the first disease association and linkage studies of this gene. As well as examining hypertension itself, we also checked whether there was any effect on mortality in the same way as tested previously for angiotensin-converting enzyme (ACE) genotypes.26
| Methods |
|---|
|
|
|---|
10% of all hypertensive patients.26
Characteristics of the groups are shown in Table 1. These studies had human ethics
approval, and all subjects gave informed consent.
|
Sib-Pair Study
Two hundred thirty-four individuals from 98 hypertensive
sibships (
2 affected sibs) were contacted by community advertising.
All were Anglo-Caucasians, mainly from eastern Australia, principally
Sydney, and had to have systolic/diastolic blood
pressure of >140/90 mm Hg and not have diabetes or renal
disease. After adjustment for 14 trios and 6 quartets,32
the weighted sib-pair number was 156. Table 1 shows their
characteristics.
Genotyping
DNA was isolated from whole blood by a modified
salting-out method.33 Genotypes for the biallelic
polymorphism were determined by polymerase chain reaction (PCR)
with the following primers: sense 5'-TGG TGC ATG CCT GTA GTC C-3';
antisense 5'-GAG GCC TCT GAG ATG TTG GTC-3'. The former was labeled
with FAM during synthesis by Bresatec (Adelaide, South Australia). The
PCR mix (25 µL) consisted of 50 ng DNA, 20 nmol each primer,
0.25 mmol/L each dNTP, 1 U AmpliTaq Gold DNA polymerase
(Perkin-Elmer), 50 mmol/L KCl, 10 mmol/L Tris-HCl, pH 8.3,
1.7 mmol/L MgCl2, and 4 µg BSA. A
"hot-start" protocol was used in which after initial denaturation
at 94°C for 5 minutes, there were 10 cycles of 94°C, 65°C, and
72°C for 1 minute each, followed by 15 cycles of 94°C, 60°C, and
72°C for 1 minute each, and finally 20 cycles of 94°C, 58°C, and
72°C for 1 minute each, finishing with a step at 72°C for 30
minutes
For the multiallelic marker, PCR primer sequences were: forward, 5'-ACC CCT GGA AGC CTA CAA CTG CAT-3' (FAM-labeled); reverse, 5'-GCC ACT GCA CCC TAG CCT GTC TCA-3'. The final PCR mix (8 µL) was composed of 50 ng DNA, 5.4 nmol each primer, 0.24 mmol/L each dNTP, 0.4 U AmpliTaq Gold, 49 mmol/L KCl, 10 mmol/L Tris-HCl, pH 8.3, and 2 mmol/L MgCl2. After an initial denaturation step at 94°C for 12 minutes, 35 cycles of 94°C, 55°C, and 72°C for 30 seconds each were performed, finishing with a 10-minute step at 72°C.
All PCR products were electrophoresed on an ABI 377 automated sequencer (Applied Biosystems), and genotypes were assigned with ABI Genotyper software.
Statistical Analysis
Genotype data were used to calculate total alleles
on all chromosomes, and these data were tested by
2 analysis with Excel (Microsoft). The
comparison of different parameters across genotypes
involved 1-way ANOVA. Linkage analysis was performed with the
use of programs suitable for complex traits,34 viz,
SPLINK, which uses allele shared identity by state (IBD) estimates
for all possible pairs in a sibship and computes probabilities for each
marker genotype when parents are not available, the Affected
Pedigree Member (APM) method, and MAPMAKER/SIBS. Linkage disequilibrium
between the markers was tested as described.35
| Results |
|---|
|
|
|---|
26 kg/m2) patients. Comparison by 1-way ANOVA
of the various parameters in Table 1 across
genotypes did not reveal any significant differences. For
example, systolic blood pressure (mean±SD, mm Hg) in
the hypertensives was 174±25, 179±25, and 170±21 for
/, +/-, and +/+ genotypes
(n=62, 22 and 5), respectively, and for diastolic pressure
was 112±17, 111±24, and 114±21. Values for plasma lipids, plasma
renin, plasma angiotensinogen, and plasma ACE were similar
to those described previously26 30 and did not differ
between genotypes (data not shown).
|
Sib-Pair Study
Minor allele frequency in hypertensive sibs was 0.17. The
biallelic marker was not very informative (information content = 0.17).
Linkage analysis of sib-pair data by SPLINK, either weighted or
unweighted, gave P=0.50, and analysis by APM produced
P=0.66. Thus each method showed no significant excess
allele sharing.
Multillelic Marker
Association Study
Frequencies of the 8 alleles in each group are shown in Table 3. Observed heterozygosity was 0.74 in
the normotensive group, 0.81 in the hypertensive group, and 0.77 in the
hypertensive sibs. Comparison of allele frequencies by
2 analysis showed no significant
difference between the groups. Blood pressure and other
parameters were also similar for each genotype.
|
The 2 markers were in weak linkage disequilibrium (D'= 70%, P=0.05) with alleles 193, 198, and 203 of the multiallelic marker begin associated with the + allele of the biallelic marker, and alleles 178, 183, 188, 208, and 213 being associated with the - allele.
Sib-Pair Study
Linkage analysis of sib-pair data by SPLINK, unweighted
and weighted, gave probability values of 0.56 and 0.57, respectively,
indicating no excess allele sharing. APM produced
P=0.4. A loglike value of 0.00 was obtained by
MAPMAKER/SIBS, and Lod score was -1.6.
Analysis in Different Age Groups
Genotype frequency is fixed from conception and
should remain constant throughout life. Any deviation with age could
indicate an effect on longevity. To test this, data in Table 2
were reanalyzed after subdivision into age groups of <50
years, 50 to 59, and
60, as done previously to reveal a deleterious
effect of the deletion allele of an ACE gene variant in
the same group.26 As can be seen in Table 2,
although frequencies were virtually identical with control in the
younger age groups, the older hypertensives had double the frequency of
the "+" allele (0.28), with correspondingly lower "-"
allele frequency (
2=7.4,
P=0.006). In contrast, the normotensives showed no
difference with age (data not shown). Comparison of -/- with -/+ and
+/+ frequencies combined produced
2=7.9,
P=0.005. The hypertensive group but not the
normotensives displayed, moreover, a significant interaction of age
with genotype: /=50.7±11.9 SD y (n=76),
/+=57.3±11.8 (n=27), and +/+=53.8±13.3 (n=6)
(P=0.05 by ANOVA). Pretreatment blood pressures were similar
for each genotype, in each age group; for example, in the older
subgroup, systolic=183±24 SD, 182±20, 180±14 for
/, /+, and +/+ (n=16, 20, and 2,
respectively); diastolic=112±15, 112±23, 113±4. All
parameters were similar for older versus younger patients,
except that pretreatment systolic pressure was higher in the
older subgroup (182±21 vs 171±26 SD mm Hg;
P=0.03).
Similar analyses in the hypertensive sibs, whose blood pressure
was lower overall (mean diastolic=103 vs 112 mm
Hg; Table 1), showed no difference across age groups ("-"
frequency: 0.15, 0.20, 0.16 for age <50, 50 to 59, and
60 years,
respectively). However, restriction to sibs with more severe
hypertension (diastolic
100 mm Hg; mean=107±10
SD) revealed a genotypic difference in the 20 sibs
60 years: viz,
0.60, 0.40, and 0.0 for /, /+, and
+/+, respectively (P=0.03 vs normotensives). For
the 38 sibs <60 years of age (with diastolic
100
mm Hg), genotype values (0.76, 0.21, and 0.03) for /,
/+, and +/+ were similar to the normotensives. Age for each
genotype of the more severely hypertensive sibs was 57±10 (SD)
years, 59±10, and 57, respectively (n=48, 20, and 1).
For the multiallelic marker, although numbers for each allele were smaller, no age-related differences could be seen (data not shown).
| Discussion |
|---|
|
|
|---|
Biallelic allele frequency in our normotensives and younger hypertensives was similar to what others have observed in unselected European whites (minor allele frequency=0.15, n=35).20 Since, in the absence of exhaustive studies, it is generally believed that results of association analyses only apply to the polymorphism tested, the present findings do not rule out hypertension association for (an)other variant(s) in or near NOS2A that is not in linkage disequilibrium with the markers tested.
The negative sib-pair linkage result suggests either that the
NOS2A locus is not linked to essential hypertension or the
size of the study group was insufficient to provide sufficient power to
reveal a small genetic contribution of NOS2A or a linked
gene to hypertension. For strong family history and disease onset
before age 55 years, relative risk to a sibling
(
s) is 3.8,38 meaning that
in a complex disease
100 sib-pairs would be sufficient to provide
90% power to show significant linkage at the Lod
3
(P
0.000139 ) level.40 For a
disease with multiple weak contributing loci (eg,
s values of
2), 156 sibs should have 90%
power to provide evidence at the Lod
2 (P
0.001)
level,40 as indeed we have found with our number of
sibs for markers on chromosome 172 and as others have
reported for the angiotensinogen locus.41
Thus a negative result from both association and linkage analysis helps provide some assurance about the validity of the conclusion reached but does not completely rule out a contribution to the disease tested.
Our 2 groups of hypertensives had similar inclusion criteria and geographic location. However, the stronger family history of hypertensives with 2 hypertensive parents may explain why their age of onset of hypertension (32±10 [SD] years) was earlier than the hypertensive sibs (43±13 years), so accounting for their lower age (53±12 [SD] vs 61±10 years) and more severe hypertension (Table 1). Moreover, the fact that age of onset for the older hypertensives (33±7 years) was similar to the younger hypertensives rules out a different pathogenesis involving late-onset disease.
There has been no previous molecular genetic study of NOS2A in hypertension, so our results add to findings for NOS1, in which an 8-allele microsatellite (heterozygosity 0.52) in exon 29 failed to show association with hypertension in Japanese patients,42 and NOS3, in which a 24-allele dinucleotide repeat (polymorphism information content 0.92) in intron 13 showed no linkage with hypertension in 269 white sib-pairs43 nor association in 88 hypertensives with 2 hypertensive parents.44 In Japanese patients, although no difference was observed for the whole group, hypertensives without left ventricular hypertrophy showed a weak (P=0.02) association with hypertension.45 Two other single-base substitution polymorphisms, in introns 18 and 23, have also proved negative for hypertension in whites,43 46 but a T/G variant in exon 7 that causes an amino acid substitution (Asp298Glu) was 16% more frequent (P=0.004).46 It displayed, however, no association with blood pressure.46 Thus results to date for NOS1 and NOS3 also provide little support for each in the pathogenesis of hypertension.
Although we found no association in the group as a whole or in younger hypertensives, in the case of the biallelic variant, older more severely affected hypertensives of either group displayed a 2-fold elevation in +/--genotype frequency and a one-third reduction in /genotype frequency. /+ hypertensives were also 7 years older than /hypertensives. No conclusion could be made about +/+ homozygotes because patient number and population frequency for this genotype was low.
A possible cause of altered genotype frequency with age may involve effects on survival or mortality. Our results would be consistent with a deleterious effect in high-risk patients with the /genotype or a survival advantage in those with the /+ genotype. What this would mean is that at the level of the gene, the promoter variant tested could affect NOS2A expression or be in linkage disequilibrium with (an)other variant(s) that confers altered promoter activity, mRNA stability, or is a sequence variant of iNOS having different enzymatic activity. Thus alteration in iNOS-mediated NO formation could affect death rate in at-risk individuals.
Depending on the tissue, cytotoxic effects of elevated iNOS activity might be either beneficial, for example, in reducing tumor growth,47 or harmful, for example, in ß-cell destruction and onset of noninsulin-dependent diabetes mellitus (NIDDM),48 atherosclerosis,49 and coronary disease.50 Infections result in an iNOS response, which may be beneficial or deleterious, depending on the pathogen.47 Survival effects could involve its immune or proinflammatory functions,47 and enhanced vasodilatory actions could be cardioprotective. The effects of iNOS therefore appear dichotomous.47 However, the greatest cause of death in patients >60 years of age with moderate to severe hypertension is heart attack and stroke.51 Atherosclerosis is an exacerbatory factor, for which iNOS has both pathogenic49 and protective52 functions. Both iNOS and ACE are elevated markedly in human coronary plaque macrophages.53 Higher iNOS levels in -/- patients could thus have a survival disadvantage.
If our results do indeed reflect an effect on longevity, the rarity of the + allele makes it difficult to say whether the + allele might be genetically dominant, that is, whether it has a similar effect in /+ and +/+ patients or whether heterozygosity provides a greater relative survival advantage than either allele alone.
In conclusion, the present work provides no support for involvement of the iNOS gene (NOS2A) in the genetics of essential hypertension but suggests that genetic variation involving a tetranucleotide repeat in the promoter is associated with mortality.
| Acknowledgments |
|---|
1
affected nontwin sib. Assistance in recruitment of other hypertensive
sibships and unrelated hypertensives, as well as blood collection and
DNA extraction was provided by Andrew Schrader, Robert Zee, Judith
O'Neill, Susan Chambers, Kazuo Suzuki, and Weiyi Zhang in the
authors' laboratory, and for 14 sibships and 16 hypertensives with 2
hypertensive parents, Sharon Quinlan, Sue Rutherford, Sharon
Boatwright, Robert Curtain, and Monique Salzmann in the laboratory of
Lyn Griffiths at Griffith University (Gold Coast), Australia. We also
thank Linda Adams, SUPAMAC, Australian Technology Park, Sydney, for
performing gene scan analysis and Dale Nyholt for advice with
some of the statistical analysis of linkage data. Received July 21, 1998; first decision September 16, 1998; accepted October 30, 1998.
| References |
|---|
|
|
|---|
2. Rutherford S, Morris BJ, Griffiths LR. In search of hypertension gene loci: a genome-wide scan using affected siblings. Annu Sci Mtg Hum Genet Soc Aust. 1997;July:15.
3.
Chartrain NA, Geller DA, Koty PP, Sitrin NF, Nussler
AK, Hoffman EP, Billiar TR, Hutchinson NI, Mudgett JS. Molecular
cloning, structure, and chromosomal localization of the human inducible
nitric oxide synthase gene. J Biol Chem. 1994;269:67656772.
4. Xu W, Charles IG, Liu L, Koni PA, Moncada S, Emson P. Molecular genetic analysis of the duplication of human inducible nitric oxide synthase (NOS2) sequences. Biochem Biophys Res Commun. 1995;212:466472.[Medline] [Order article via Infotrieve]
5. Mayer B, Hemmens B. Biosynthesis and action of nitric oxide in mammalian cells. Trends Biochem Sci. 1997;22:477481.[Medline] [Order article via Infotrieve]
6.
Mattson DL, Maeda CY, Bachman TD, Cowley AW. Inducible
nitric oxide synthase and blood pressure. Hypertension. 1998;31:1520.
7.
Node K, Kitakaze M, Yoshikawa H, Kosaka H, Hori M.
Reduced plasma concentrations of nitric oxide in individuals with
essential hypertension. Hypertension. 1997;30:405408.
8. Devlin AM, Brosnan J, Graham D, Morton JJ, McPhaden AR, McIntyre M, Hamilton CA, Reid JL, Dominiczak AF. Vascular smooth muscle cell polyploidy and cardiomyocyte hypertrophy due to chronic NOS inhibition in vivo. Am J Physiol. 1998;274:H52H59.
9. Singh A, Sventek P, Lariviere R, Thibault G, Schiffrin EL. Inducible nitric oxide synthase in vascular smooth muscle cells from prehypertensive spontaneously hypertensive rats. Am J Hypertens. 1996;9:867877.[Medline] [Order article via Infotrieve]
10.
Chou TC, Yen MH, Li CY, Ding YA. Alterations in nitric
oxide synthase expression with aging and hypertension in rats.
Hypertension. 1998;31:643648.
11. Lippoldt A, Gross V, Schneider K, Hansson A, Nadaud S, Schneider W, Bader M, Yagil C, Yagil Y, Luft FC. Nitric oxide synthase and renin-angiotensin system gene expression in salt-sensitive and salt-resistant Sabra rats. Hypertension. 1997;30(part 1):409415.
12. Chen PY, Sanders PW. L-Arginine abrogates salt-sensitive hypertension in Dahl/Rapp rats. J Clin Invest. 1991;88:15591567.
13.
Chen PY, Gladish RD, Sanders PW. Vascular smooth muscle
nitric oxide synthase anomalies in Dahl/Rapp salt-sensitive rats.
Hypertension. 1998;31:918924.
14. Hilbert P, Lindpainter K, Beckmann JS, Serikawa T, Soubrier F, Dubay C, Cartwright P, De Gouyen B, Julier C, Takahashi S, Vincent M, Ganten D, Georges M, Lathrop GM. Chromosomal mapping of two genetic loci associated with blood-pressure regulation in hereditary hypertensive rats. Nature. 1991;353:521529.[Medline] [Order article via Infotrieve]
15. Jacob HJ, Lindpainter K, Lincoln SE, Kusumi K, Bunker RK, Mao Y-P, Ganten D, Dzau VJ, Lander ES. Genetic mapping of a gene causing hypertension in the stroke-prone spontaneously hypertensive rat. Cell. 1991;67:213224.[Medline] [Order article via Infotrieve]
16. Dubay C, Vincent M, Samani NJ, Hilbert P, Kaiser MA, Beressi JP, Kotelevtsev Y, Beckmann JS, Soubrier F, Sassard J, Lathrop GM. Genetic determinants of diastolic and pulse pressure map to different loci in Lyon hypertensive rats. Nat Genet. 1993;3:354357.[Medline] [Order article via Infotrieve]
17. Pravenec M, Gauguier D, Schott JJ, Buard J, Kren V, Bila V, Szpirer C, Szpirer J, Wang JM, Huang H, St Lezin E, Spence MA, Flodman P, Printz M, Lathrop GM, Vergnaud G, Kurtz T. Mapping of quantitative trait loci for blood pressure and cardiac mass in the rat by genome scanning of recombinant inbred strains. J Clin Invest. 1995;96:19731978.
18.
Schork NJ, Kreiger JE, Trolliet MR, Franchini KG, Koike
G, Kreiger EM, Lander ES, Dzau VJ, Jacob HJ. A biometrical genome
search in rats reveals the multigenic basis of blood pressure
variation. Genome Res. 1995;5:164172.
19. Nunokawa Y, Ishida N, Tanaka S. Promoter analysis of human inducible nitric oxide synthase gene associated with cardiovascular homeostasis. Biochem Biophys Res Commun. 1994;200:802807.[Medline] [Order article via Infotrieve]
20. Bellamy R, Hill AVS. A bi-allelic tetranucleotide repeat in the promoter of the human inducible nitric oxide synthase gene. Clin Genet. 1997;52:192193.[Medline] [Order article via Infotrieve]
21. Xu W, Liu L, Emson PC, Harrington CR, Charles IG. Evolution of a homopurine-homopyrimidine pentanucleotide repeat sequence upstream of the human inducible nitric oxide synthase gene. Gene. 1997;204:165170.[Medline] [Order article via Infotrieve]
22.
Michel D, Chatelain G, Herault Y, Brun G. The long
repetitive polypurine/polypyrimidine sequence (TTCCC)48 forms DNA
triplex with PU-PU-PY base triplets in vivo. Nucleic Acids
Res. 1992;20:439443.
23. Nickol JM, Felsenfeld G. DNA conformation at the 5' end of the chicken adult ß-globin gene. Cell. 1983;35:467477.[Medline] [Order article via Infotrieve]
24.
Takeuchi K, Alexander RW, Nakamura Y, Tsujino T, Murphy
TJ. Molecular structure and transcriptional function of the rat
vascular AT(1a) angiotensin receptor gene. Circ
Res. 1993;73:612621.
25. Bennet ST, Todd JA. Human type I diabetes and the insulin gene: principles of mapping polygenes. Annu Rev Genet. 1996;30:343370.[Medline] [Order article via Infotrieve]
26. Morris BJ, Zee RYL, Schrader AP. Different frequencies of angiotensin-converting enzyme genotypes in older hypertensive individuals. J Clin Invest. 1994;94:10851089.
27. Morris BJ, Jeyasingam CL, Zhang W, Curtain RP, Griffiths LR. Influence of family history on frequency of glucagon receptor Gly40Ser mutation in hypertensive subjects. Hypertension. 1997;30:16401641.
28. Zee RYL, Ying L-H, Griffiths LR, Morris BJ. Association and linkage analyses of restriction fragment length polymorphisms for the human renin and antithrombin III genes in essential hypertension. J Hypertens. 1991;9:825830.[Medline] [Order article via Infotrieve]
29. Morris BJ, Zee RYL, Ying L-H, Griffiths LR. Independent, marked associations of alleles of the insulin receptor and dipeptidyl carboxypeptidase-1 genes with essential hypertension. Clin Sci. 1993;85:189195.[Medline] [Order article via Infotrieve]
30. Schrader AP, Zee RYL, Morris BJ. Association analyses of NsiI RFLP of human insulin receptor gene in hypertensives. Clin Genet. 1996;49:7478.[Medline] [Order article via Infotrieve]
31. Chambers SM, Morris BJ. Glucagon receptor gene mutation in essential hypertension. Nat Genet. 1996;12:122.Letter.[Medline] [Order article via Infotrieve]
32. Hodge SE. The information contained in multiple sibling pairs. Genet Epidemiol. 1984;1:109122.[Medline] [Order article via Infotrieve]
33.
Miller SA, Dykes KK, Polesky HF. A simple salting out
procedure for extracting DNA from human nucleated cells. Nucleic
Acids Res. 1988;16:1215.
34. Davis S, Weeks DE. Comparison of nonparametric statistics for detection of linkage in nuclear families: single-marker evaluation. Am J Hum Genet. 1997;61:14311444.[Medline] [Order article via Infotrieve]
35. Thompson EA, Deeb S, Walker D, Motulsky AG. The detection of linkage disequilibrium between closely linked markers: RFLPs at the AI-CIII apolipoprotein genes. Am J Hum Genet. 1988;42:113124.[Medline] [Order article via Infotrieve]
36. Khoury MJ, Beaty TH, Cohen BH. Fundamentals of genetic epidemiology. In: Kelsey JL, Marmot MG, Stolley PD, Vessey MP, eds. Monographs in Epidemiology and Biostatistics. Vol 19. New York, NY: Oxford University Press; 1993.
37.
Lander ES, Schork NJ. Genetic dissection of
complex traits. Science. 1994;265:20372048.
38. Williams RR, Hunt SC, Hasstedt SJ, Hopkins PN, Wu LL, Berry TD, Stults BM, Barlow GK, Schumacher MC, Lifton RP, Lalouel JM. Are there interactions and relations between environmental factors predisposing to high blood pressure? Hypertension. 1991;18(suppl I):I-29I-37.
39. Lander E, Kruglyak L. Genetic dissection of complex traits: guidelines for interpreting and reporting linkage results. Nat Genet. 1995;11:241247.[Medline] [Order article via Infotrieve]
40. Weeks DE, Lathrop M. Polygenic disease: methods for mapping complex disease traits. Trends Genet. 1995;11:513519.[Medline] [Order article via Infotrieve]
41. Jeunemaitre X, Soubrier F, Kotelevtsev YV, Lifton RP, Williams CS, Charru A, Hunt SC, Hopkins PN, Williams RR, Lalouel J-M, Corvol P. Molecular basis of human hypertension: role of angiotensinogen. Cell. 1992;71:169180.[Medline] [Order article via Infotrieve]
42. Takahashi Y, Nakayama T, Soma M, Uwabo J, Izumi Y, Kanmatsuse K. Association analysis of TG repeat polymorphism of the neuronal nitric oxide synthase gene with essential hypertension. Clin Genet. 1997;52:8385.[Medline] [Order article via Infotrieve]
43. Bonnardeaux A, Nadaud S, Charru A, Jeunemeitre X, Corvol P, Soubrier F. Lack of evidence for linkage of the endothelial cell nitric oxide synthase gene to essential hypertension. Hypertension. 1995;91:96102.
44. Friend LR, Morris BJ, Gaffney PT, Griffiths LR. Examination of the role of nitric oxide synthase and renal kallikrein as candidate genes for essential hypertension. Clin Exp Pharmacol Physiol. 1996;23:564566.[Medline] [Order article via Infotrieve]
45. Nakayama T, Soma M, Takahashi Y, Izumi Y, Kanmatsuse K, Esumi M. Association analysis of CA repeat polymorphism of the endothelial nitric oxide synthase gene with essential hypertension. Clin Genet. 1997;51:2630.[Medline] [Order article via Infotrieve]
46. Lacolley P, Gautier S, Poirier O, Pannier B, Cambien F, Benetos A. nitric oxide synthase gene polymorphisms, blood pressure and aortic stiffness in normotensive and hypertensive subjects. J Hypertens. 1997;16:3135.
47. Nathan C. Inducible nitric oxide synthase: what difference does it make? J Clin Invest. 1997;100:24172423.[Medline] [Order article via Infotrieve]
48. Shimabukuro M, Ohneda M, Lee Y, Unger RH. Role of nitric oxide in obesity-induced ß cell disease. J Clin Invest. 1997;100:290295.[Medline] [Order article via Infotrieve]
49. Buttery LDK, Springall DR, Chester AH, Evans TJ, Standfield N, Parums DV, Yacoub MH, Polak JM. Inducible nitric oxide synthase is present within human atherosclerotic lesions and promotes the formation and activity of peroxynitrite. Lab Invest. 1996;75:7785.[Medline] [Order article via Infotrieve]
50.
Ravalli S, Albala A, Ming M, Szabolcs M, Barbone A,
Michler RE, Cannon PJ. Inducible nitric oxide synthase expression
in smooth muscle cells and macrophages of human transplant
coronary artery disease. Circulation. 1998;97:23382345.
51. Neaton JD, Kuller L, Stamler J, Wentworth DN. Impact of systolic and diastolic blood pressure on cardiovascular mortality. In: Laragh JH, Brenner BH, eds. Hypertension. Pathophysiology, Diagnosis, and Management. 2nd ed. New York, NY: Raven Press; 1995:127144.
52. Rikitake Y, Hirata K, Kawashima S, Akita H, Yokoyama M. Inhibitory effect of inducible type nitric oxide synthase on oxidative modification of low density lipoprotein by vascular smooth muscle cells. Atherosclerosis. 1998;136:5157.[Medline] [Order article via Infotrieve]
53. Ohishi M, Fennessy PA, Ousting GJ, Mendelsohn FAO, Zhuo JL. Expression of the renin-angiotensin system and nitric oxide synthase during the development of human coronary atherosclerosis. Abstract Presented at: 21st Annual Scientific Meeting of the High Blood Pressure Research Council of Australia; December 1012, 1998; Melbourne, Australia.
This article has been cited by other articles:
![]() |
G. T. Yocum, J. G. Gaudet, S. S. Lee, Y. Stern, L. A. Teverbaugh, R. R. Sciacca, C. W. Emala, D. O. Quest, P. C. McCormick, J. F. McKinsey, et al. Inducible Nitric Oxide Synthase Promoter Polymorphism Affords Protection Against Cognitive Dysfunction After Carotid Endarterectomy Stroke, May 1, 2009; 40(5): 1597 - 1603. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Yamada, M. Utsunomiya, K. Inoue, K. Nozaki, S. Inoue, K. Takenaka, N. Hashimoto, and A. Koizumi Genome-Wide Scan for Japanese Familial Intracranial Aneurysms: Linkage to Several Chromosomal Regions Circulation, December 14, 2004; 110(24): 3727 - 3733. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Elbaz and A. Alperovitch Bias in Association Studies Resulting from Gene-Environment Interactions and Competing Risks Am. J. Epidemiol., February 1, 2002; 155(3): 265 - 272. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Loscalzo Salt-Sensitive Hypertension and Inducible Nitric Oxide Synthase: Form-Function Dichotomy of a Coding Region Mutation, Mutatis Mutandis Circ. Res., August 17, 2001; 89(4): 292 - 294. [Full Text] [PDF] |
||||
![]() |
E. D. Frohlich Risk Mechanisms in Hypertensive Heart Disease Hypertension, October 1, 1999; 34(4): 782 - 789. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Soubrier Nitric Oxide Synthase Genes : Candidate Genes Among Many Others Hypertension, April 1, 1999; 33(4): 924 - 926. [Full Text] [PDF] |
||||
![]() |
W.-Z. Ying, H. Xia, and P. W. Sanders Nitric Oxide Synthase (NOS2) Mutation in Dahl/Rapp Rats Decreases Enzyme Stability Circ. Res., August 17, 2001; 89(4): 317 - 322. [Abstract] [Full Text] [PDF] |
||||
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1999 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |