Oxide Synthase Gene Polymorphisms in Dilated Cardiomyopathy

Türk Kardiyol Dem Arş 2004:32:295-301

Angi o tensin -Converting Enzyın e, Angi o tensin II Receptor, Apolipoprotein E and Endothelial Constitutive Nitric

Oxide Synthase Gene Polymorphisms in Dilated Cardiomyopathy

Hakan ÖZHAN, MD, Mustafa ZUNGUR\ MD, Mehmet Y AZI CI, MD, Ramazan AKDEMİR, MD, Hüseyin GÜNDÜZ

b,

MD, Enver

ERBİLEN,

MD, Sinan ALBA YRAK, MD,

Haşim

MUTLlf, MD,

Cihangir UYAN

b,

MD, İhsa n KARA

d,

MD, Güler KAYA

d,

PhD

Abani İ zzet Baysal University Diizce Faculty of Medicine, Diizce,

a Özel Çağ Hastanesi Ankara, b Aba nt İ zzet Baysal University Bolu Faculty of Medicine, Bolu cJstanbul University Cerrahpaşa Medical Faculty, Istanbul

d Istanbul University lnstitlllefor Medical Researclı, Istanbul, Turkey

Summary

Genetic factors are hypothesized to contrihute to the dilated cardiomyopathy (DCM) susceptibility, evenin spo- radic cases. Abundant repo rts have investigated the assodation between various gene po/ym01phisms and the phenotypic expressian of DCM. The ai m of the

prese1ıt

study is to assess the effect of fo ur candieiate gene poly- mOJphisms (1166 Al C po/ym01phism of the angiatensin ll type 1 receptar (AGTR1) gene, !ID po/ymorphism of angiatensin canverring enzyme (ACE) gene,

endotlıelialnitric

oxide synthase (ec-NOS) and apolipoprotein E (APOE genes) on the pathogenesis of dilated

cardiomyopatlıy.

We studied 76 consecutive patients

(nıean

age 58±12) with DCM and 88

lıealthy

age- and sex-marcheel control subjects (mean age 59±12). All patients were assessed by 2-dimensiona/ echocardiography and all had /eft ventricular dilatation (e nd diastolic

elianıeter

>55 mm) and impaired systo!ic f unction ( ejection fraction <40%).

All patients were catheterized. Patients having normal coronary arteries were classified as

'idiopatlıic'

and the remaining group as 'ischemic' DCM. Patients with specific heart muscle disease, iso/ateel right ventricu!ar di-

/atatiorı

and valvu/ar or pericardia! disease were excluded.

Deoxyribonııcleic

acid (DNA) was isofateel from blood samples, and genotypes were determined by specific

polynıerase

chain reaction (PCR) and separation of amplified fragments by agarose gel electrophoresis.

W e compareel genotypes and allelefrequencies, echocardiographic measurements, biochemical variab/es in our patients and control group . Age, sex, body mass index differences were statistical/y non-significant. APO E ge- notypes and allele frequencies were significantly different in patients with DCM. Multiple regression analyses demonstrated taek of independent association. Subgroup analysis revealed that the four canelidare gene poly- morphisms were not associated with ischemic or idiopathic DCM .

Conclusions: No significant association exists hetween dilated cardiomyopathy and polymorphism of the AGTR1, ACE, ecNOS and APOE gene polymorphisms. (Türk Kardiyol Dern

Arş

2004; 32: 295-301)

K ey words: AGTR1 gene, ACE gene, ecNOS gene, APOE gene, polymOJphism, dilated cardiomyopathy

Özet

Dilate Kardiyomiy opatili Hastalarda A ngiatensin

Dönüştürücü

Enzim, A ngiaten sin Il R eseptör, Apolipoprotein E ve Endotelyal Kon stitiitif Nitrik Oksit Se nlaz Geni Polimorfizmi

Amaç: Dilate kardiyomiyopati (DCM ) sol yada her iki ventrikülün

sistolikfonksiyonlarımn bozulması

ve

geniş­

lemesi ile karakterize bir

hasta/ıktu·.

Ailesel kökenli DCM 'nin tammlanmasmdan sonra ailesel olmayan DCM

Address for Correspondence: Hakan Özhan, MD, Abant İzzet Baysal Üniversitesi Düzce Tıp Fakültesi Kardiyoloji Kliniği Konuralp, Düzce. Turkey Tel: (90) 532 558 2873 Fax: (90) 380 541 4486 e-mail:ozhanhakan@yahoo.com

Received: ll March, accepted: 8 June 2004

Türk Kardiyol Dem Arş 2004; 32:295-301

olgulan için de genetik faktörlerin rol

oynayabileceği düşünülmüş

ve konuyla ilgili

araştırmalar yapılmıştir.

Makalemizde ülkemizde

yaşayan

DCM'li olgularda ,

lzastalığm

patofizyolojisinde rol

oynaması

muhtemel dört t aday genin polimOifizmleri

araştmlnuştir

(Angiotensin

dönüştürücü

enzim (ACE) /ID p olimOifizmi, angiaten-

sin II reseptör (AGTRJ) 1166 AIC polimOifizmi, apolipoprotein E (APOE) ve endotelyol konstitütif nitrik oksit sentaz ( ecNOS) ge ni po!imOij'izmi).

Ortalama

yaşı

58±12 olan

ardişık

76 hasta ve

yaş

ortalamasi 59±12 olan 88 kontrol grubu

çalışmaya alindı.

Bütün hastalara ve kontrol grubuna ekokardiyografik

çalışma yaprldı.

DCM

tamsı

için ekokardiyografi k olarak end-diastolik

çapın

>55mm ve

ejeksiyonfraksiyonwıun

<%40 altmda

olması

kriter

almdı.

Yine hasta grubuna koroner anjiografi yapilarak hastala r iskemik ve idyopatik DCM

gruplarına ayrıldı.

Spesifik kalp

kası hastalı­

ğı,

izo le

sağ

ventrikül

genişlemesi,

kapak ve perikard

hastaliğı

olanlar

çalışma dışında

tutuldu . Hasta ve kontrol g rubunun kan hücrelerinden deoxiribonükleik asit (DNA) spesif ik polimeraz zincir reaksiyonu (PCR ) yöntemi ile genetik analiz

yapıldı.

Gen distribüsyonu ki kare testi ile

değerlendirildi. Bağımsız

risk için multivariate reg- resyon analizi

uygulandı.

0,05

altındakip değerleri

istatistiks el olarak

anlamlı

kabul edildi.

Sonuçlar: Hasta ve kontrol grubunun allel

sıklikları,

ekokardiyograf i, biyokimya analizi

sonuçları

ve demogra - fik verileri

karşilaştmldı.

APO E gen allel

Siklığına

ait

dağılım

her iki grupta

farklılık

gösterse de regresyon analizi

sonuçlarına

göre bu

farklılığın bağtmsiz

bir risk

oluşturmadığı

gözlendi. (Türk Kardiyol Dern

Arş

2004; 32: 295-301)

Anahtar kelimeler: AGTRJ geni, ACE geni, ecNOS geni, APOE geni, polimorfizm, eliiate kardiyomiyopati

Dilated cardiomyopathy is a myocardial disease characterized by impaired systolic function and dilation of the left or both ventricles <

¹

l. Despite recent advances in medical and surgical th era- pies, it remains an important cause of mortality and morbidity and is a leading indication for heart transplantation. The dilated cardiomyopa- thies are a heterogeneous group of disorders with dif ferent inheritance patterns, including autosomal dominant (-23%), X-linked (-5%), autosomal recessive, and mitochondrial trans- mission. Approximately 30% of all DCM is thought to be inherited, while 70% is sporadic.

A high perce ntage of sporadic cases appear to be due to acquired disease, including myocardi- tis or coronary artery disease and about 50% of them are idiopathic in origin

<¹

l.

Several genetic loci have been identified in rare monogenic forms of the disease. These findings

!ed to the hypothesis that genetic factors might also be involved in sporadic forms of the dis- ease. All genes cod ing for proteins involved in biochemica l or physiological abnormalities of cardiac function are potential candidates for idi- opathic DCM.

The angiatensin I-converting enzyme (ACE) in- sertion/deletion (ID) <2l, the angiotensinogen,

296

the aldosterone synthase (CYP11B2), the tumor necrosis factor-alph a, the transforming growth factor beta 1, the endothelial nitric oxide syn- thase (ecNOS) , the brain natriure tic peptide genes (3l and endothelin receptor type A gene

<⁴

l were some of the polymorphisms in the genes that carry the potential to influence disease pathogenesis.

In the present study, we sought to investigate the role of polymorphi sms of four candidate genes; 1166 A/C pol ymorphism of the AGTRl gene, I/D polymorphism of ACE gene, ec-NOS and APOE genes in the development and pro- gression of DCM in Turkish population.

METHODS

Ethics approval for the study was obtained from the Duzce and Cerrahpasa Medica l School

comınittees,

and each subject s igned written in formed consent for the study.

76 patients w ith DCM (LV ejection fraction LVEF

<40% at the initia l assessment and LV end diasto lic diameter L VEDD >55 mm) as determined us ing transthoracic echocardiography were inc luded in the study. Patients were excluded from participation in the study if they had the follow ing crite ria:

priınary

valvular disease, e linical or echocardiographic fea-

tures consis tent with an obstructive, hypertrophic or

ll

restrictive cardiomyopathy, pericardial disease, pri- mary hepatic, rena l, neurological, pulmonary or en- docrine disease, and arrhythmias that cou ld alter L VEF. All patients were performed card iac catheter- ization. Pati ents having norma l coronary arteries were classified as 'idiopathic' and the other group as 'ischemic' DCM.

A control group of 88 apparently healthy unrelated age and sex

nıatched

subjects were randamly recruit- ed from the general population. These s ubjects had a elinical history recorded; general examinations per- formed, and excluded if they had diabetes ınellitus, hypertens ion or a fami ly history of coronary artery disease. All the subjects were screeneel by transtho- racic echocardiography for the presence of DCM or other excl us ion criteria.

Genotyping: Genomic DNA was pre pared from white blood cells by phe nol extracti on. Polymor- phi sms inves tigated were an insertion (1)/deletion (D) polymorphism in intran 16 of the ACE oene· a

o '

nucleotide substitution (A+ I I 66C) in the AGTRI gene, 27-bp repeats in intran 4 of the ecNOS gene and three d ifferent a lle les (E2 , E3 and E4) encoded by APOE gene. Extracted DNA was subjecteel to PCR under s tandard cond itions by using primer pair's specific to the analyzed region.

Reactions were performed in a total volume of 50 ul co nt~inin g 1 f..l g of genomi c DNA, 40 pmol of ea~h primer, 0.2 mmoi/L of each deoxynuc leoside tri- phosphate, 1.25 U of Taq DNA po lym erase, 50 mmol/L KCl , 1.5

mınoi/L

MgCI

2,

and I O

nımol/L

Tris-HCI (pH 8.3). The the rmocycling procedure was performed with a gene a mplificatory system and consisted of initial denaturation at 94°C for 4

ınin­

utes, 35 c ycles of denaturation at 94°C for 1 minute annealing at 56°C for ı minute , extension at 72°C for 2 minutes, a nd a fina! exte ns ion at 74 °C for 7

minuıes.

The PCR

producıs

were analyzed by 2%

agarose gel e lectrophores is and visualized by ethidi- um bromide staining.

The ACE gene insertion/deletion (I/D) polymor- phis m was detected by a polymerase cha in reaction (PCR) technique us ing ol igonucleotide primers flanking th e insertion seque nce and insertion-specif- ic primer pairs as previous ly deseribed

(5).

PCRs demo ns trating the s ing le bas e s ubstitution from Al 166 to Cl l66 of AGTR J gene were carried out using pri mers upstream 5'TTGAGGTTGAGT- GACATGTTCGA - 3' and down s tr e am

5'CGGTTCAGTCCACATAATGCA-3'. '

H. Öz/ımı er al: Gene Polym01plıisms in D ilared Cardiomyoparlıy

Endothelial constitutive ecNOS genotypes were de- termined by the PCR with oligonucleotide primers (upstream, 5'-AGGCCCTATGGTAGTGCCTTT -3'·

downstream, 5'-TCTCTT AGTGCTGTGGTCAT-3') that flank the region of the 27-bp direct repeat in in- tran 4 as deseribed previously , with

nıinor ınodifica­

tions . The large allele, e cNOS4b, contained 5 tan - dem 27 -bp re pea ts of the cansens us sequenc e [GAAGTCT AGACCTGCTGC(A/G)GGGGTGAG];

the first 3 repeats contained A and the las t 2 con- tained G as the l 9th base of the 27-bp repeat. Th e smaller allele, ecNOS4a, contained 4 repe ats; the first 2 re pea ts had A and the Ias t 2 had G as the ı 9th base of the repeat. PCR analys is of

genonıic

DNA generateel fragme nts of 393 or 420 bp, carres pand- ing to the ecNOS4a and ecNOS4b alleles, respec- tively.

The

upstreanı

primer used in the genotyping of the APOE loc us was 5'-TCCAAGGAGCTG- CAGGCGGCGCCA-3' and the downs tream primer w a s 5'-ACAGAA TTCGCCCCGGCCTGGT A- CACTGCCCA-3'. The 227-base pair (bp)

polynıe­

rase chain reaction products were separate ly digest- ed by restriction

enzyınes

and resolved by electro- phoresis in 2 % agarose gel.

Statistical Analysis: Data were analyzed us ing the SPSS statis tical software. All e le freque ncies were

~sti~ated

by gene counting. Hardy-W einoe rg equi-

lıbrıum

was testeel by chi-squa re analys is. Genotype distribu tions were compareel between cases and con- trols by unpaired Student's t test. Yates corrections were taken

inıo

acco unt. The re lative risk was es ti- mated from an odd s ratio cal cula tion. Assoc iation between polymorphisms and case/co ntrol status was also testeel by means of multiva riate logis tic regres- sion analys is controlling for age, gende r anel di ffer- ent covariates. A p value <0.05 was cons ide red sta- ti s tically s ig nificant. Continuous data werc ex- pressed as mean±S.D.

RESULTS

We studied 76 consecutive patients (mean age 58±12) with DCM and 88 healthy age and sex matched control s ubj ects (m ean age 59± ı 2).

Characteri stics of patients and control subjects

are presented in Table 1. Compared to control

subjects, patients had a higher ratio of tobacco

and alcohol consumption, and a higher preva-

Tiirk Kardiyol Dem Arş 2004; 32:295-301

Tablo 1. Characteristics

ojtlıe

study population

Patients with Control DCM (n:76) (n:88)

Age (years) 58,4±12,1 58,8±11,9

BM! (kg/ııı²) 25,3±4,4 25,5±4

Male (%) 78,9 71,2

Sınokers (%) 71,1 43,2

Alcohol history(%) 27,6 5,7

DM history(%) 19,7

o

Hypertension (%) 39,5

o

Obesity (%) 10,5 4,6

Family history of CAD(%) 35,5

o

Pvalue

0,625 0,578 0,278

<0,01

<0,01

<0,01

<0,01

<0,01

<0,01

frequencies were s ignificantly diffe rent among patients and control group.

We further investigated a dominant and re- cessive model for APOE gene polymor- phism where the major E3 allele was the ref- erence allele. Dominant model did not show any significant difference between patients and controls where as the recessive tra it for E3 demonstrated an association with DCM (Table 3).

(DCM: dilated cardiomyopatlty, BM/: body mass index, DM: diabetes

nıellittıs. CAD: coronary artery diseae. Age and BM/ are expressed as mean

±

SD)

Mult ivariate logist ic regress ion analyses were performed to adjust r is k factors, in which age, gender, diabetes, hypertension, hype rlipidemia, fam ily histo ry of coronary artery disease, sm ok ing history, alcohol in- take were independent variables and DCM

lence of diabetes mellitus, hypertension and fami ly hi story of coronary artery disease. 35 pa- tients had no significant stenos is in their coro- nary arteries and classified as idiopat hic DCM.

The rest 41 patients we re grouped as isc hemic DCM. T he echocardiographic examination of the DCM patients revealed a mea n left ventric- ula r ejection f rac tion (LVEF) of 27,24 ± 13,75%, and the mean end-diastolic diameter w as 7,25 ± 0,93 mm.

Distribution of genotypes of the four candid ate genes among DCM patie nts and control sub- jects are presented in Table 2. There was no de- viation from Hardy-We inber g equilibrium for any of the polymorphisms considered. Poly- morphisms of ACE, AGTRl and ecNOS genes exhibited no s ignifi cant difference of genotype distributi on. T he all ele frequencies of ACE /, AGTR l a, ecNOS b and APO E3 were 0,33/0,79/0,83/0,74 in DCM grou p and 0,29/0,73/0,87/0,90 in control group respective- ly. The allele frequenc ies of ACE, AGTR I and ecNOS genes did not differ significantly be- tween cases and controls when Yates correc- tions were taken into account.

However th e distribution of the APOE 22/23/24/33/34/44 ge notypes and E2/3/4 allele

was depe ndent variab le remained non-s ig- nificant. We further investigated whether poly- morphisms were associated with the etiology of DCM, but again there were no significant dif- ferences between subgroups.

D ISCUSSION

The present study indicate t hat polymorphi sms of ACE, AT, APO E and ecNOS genes are not related with DCM in T urkish population. T he ratianale be hind the selec tion of the genes that were investigated in our study was the poss ibil- ity of association of these polymorphisms with DCM. Many investigations reported that th e proteins e ncoded by these genes play im portant roles in the patophysiology of heart fai lure.

It is well known that the renin-angiotens in sys- tem is a key malecul ar system in the pathegene- sis of heart failure. B lood A CE level large ly changes with the insertion (I) ordeletion (D) of 287 base pairs in intron 16 of th e gene for ACE

(5).

ACE tissue activity also is affected by ACE gene polymorphism

(6).

In 1992, Cambi en et a l

<7)

first reported the D all ele of th is polymor-

phism as a potential risk factor for the develop-

ment of myocardial infarction. Since th en,

•

H. Özlıan et al: Gene Polymmplıisnıs in Di/at ed Cardiomyopatlıy

Tab/e 2. Distribution of genotypes of

tlıe

four candidate ge11es amo11g DCM patie11ts a11d co11trol subjects

heart fai lure due to idi opathic DCM, s uggesting that the fa iling human heart is exposed to increased con- centratio ns of angiatensin-II

0²

> . The polymorphi sm investigated in the present study had been previous- ly suggested to be involved in sus- ceptibility to myocardial infaretion

(13)_

However we did not find any association betwee n DCM and AGTR 1 polymorphism.

Genotypes DCM (total) DCM DCM Control

(n:76) (ischemic) (n:41) (idiopathic) (n:3S) (n:88)

ACE II 8 (10%) 4 (10%) 4 (ll%) ı ı (12%)

ACE ID 33 (43%) 16(39%) 17 (49%) 28 (32%)

ACE

DD

35 (54%) 21 (51%) 14 (40%) 49 (56%)

P Value 0,309 0,701 0,207

AR aa 46 (60%) 23 (56%) 23 (65%) 46 (53%)

AR ac 29 (38%) 17 (41%) 12 (34%) 37 (42%)

AR cc ı (2%) ı (2%)

o

5 (5%)

P Value 0,25 0,7 0,205

NOS aa ı (1%)

o

ı (3%)

o

NOS ba 24 (32%) 13 (32%) ı ı (32%) 23 (26%) NOS bb 51 (67%) 28 (68%) 23 (65%) 65 (74%)

PValue 0,398 0,51 ı 0,223

APO e23 12(16%) 6 (15%) 6(17%) 7 (8%)

APO e24

o o o

2(2%)

APO e33 41 (54%) 21 (51%) 20 (57%) 73 (83%) APO e34 ı 9 (25%) 12 (29%) 7 (20%) 6(7%)

AP0e44 4(5%) 2 (5%) 2 (6%)

o

P Value <0,001 <0,001 0,007

(DCM: dilated cardiomyopatlıy, ACE: angiatensin converting enzyme, AR: angiaten- sin ll receptor, NOS: nitric oxide symlıase. APO:apo/ipoprotein)

The human ecNOS gene is located on chromosome 7q35-36 and com- prises 26 exons that span 21 ki lo- hases

<14

> . The

polyınorphic

region s in the ecNOS gene

ınay

influence the amount of nitric oxide synthase enzyme transcripted, leading exces- sive production of ni tric ox ide de- pressing myocardial contractility.

Nitric oxide is a powerfu l vasoac- tive molecule produced from L-argi- nine by three distinct nitric oxide synthase e nzymes . Two co nstitu- ti vely present enzymes are found in ne uronal and endothelial ce lls, re- spectively. The e ndothelial isoform NOS3 is also constitutively ex- pressed in cardi ac myocytes

(I5)

and

many ar ticles have re ported an association of the D allele with the development of left ven- tricular hypertrophy

<8_>

and hypertrophic cardi- omyopath y

(9)_

The I/ D polymorphism of the ACE gene was the f irst genetic factor reported to be associated with non-familial idiopathic DCM

cıoı.

But, thi s finding failed to be con- firmed in later studi es <

2 •4•1 1>

and in the present study.

AGTR l polymorphism may be invo lved in the susceptibility of DCM because a ngiatensin ef- fects on receptar !eve!. The AGTR 1 has been shown to be selectively down-regulated in fai l- ing left ventricle from patients with end-stage

its enhanced basa! production has been reported in patients with heart failure

(I6l.

However, the Cardigene study group

<4 >

could not confirm th e hypothes is that ecNOS poly- morphi sm leads DCM. We did not also find any association between ecNOS

polymorphisın

and DCM in Turkish population. One of the reason and our investigation could not confirm this hy- pothesis. The reason

ınight

be the presence of multiple polymorphic regions in the gene and one should in vestigate all of them separate ly before coming up with a certain concl usion.

ApoE is synthesized endogenously in foam

cells and after stimulation by extracellular lipid-

free apoA-L This facilitates cholesterol efflux

Tiirk Kardiyol Dem Arş 2004; 32:295-301

Tab/e 3. Odds ratios for DCM

assımıing

a dominant and recessive genetic modelfor EJ allele

in the pathophysiology of th e "ischemic" form of DCM. We observed an in- creased E4 di stribution among DCM patients (both in idiopathi c and ischemic form s) however we could not confirm that it is an in- dependent risk factor.

DOMINANT MODEL FOR E3 ALELE

Allele frequency OR 95% CI P value

DCM (total) vs. control 0.94/0.98 2.38 0.42-13.4 0.548 lschemic DCM vs. control 0.95/0.98 2.2 0.3-16.2 0.803 ldiopathic DCM vs. control 0.94/0.98 2.6 0.35-19.1 0.684

RECESSIVE MODEL FOR E3 ALLELE

DCM (total) vs. control 0.54/0.83 4.1 2.03-8.49 <0.001

lschemic DCM vs. control 0.51/0.83 4.6 2-10.5 <0.001

ldiopathic DCM vs. control 0.57/0.83 3.65 1.52-8.71 0.006 (DCM: dilated cardiomyopatlıy. OR: odds ratio, Cl: confidcmce interml)

Finally, the authors

adınit

that the sample size of the present stud y is relatively low. But we should remind the readers that it is the first paper in the Iiterature inves-

from lip id-laden foam cells, within the intima of Iesion, into c irculation via HDL-containing apoA-1 . Exogenous apoE can assist in choleste- rol tran sport from lesionaJ foam cells as an ex- tracellul ar, free cholesterol acceptor.

ApoE also di rectly modi fies macrophage and T- Iymphocyte-mediated immune responses to in-

flammatoı·y

atherosclerosis. The production of apoE in macrophages is regulated by inflamma- te ry cytokines, interferon -, and tumor necros is factor- a 0

7).

In humans, apo E exists in 3 alle lic fo rms: E2 (Cysl l 2-Cys l5 8), E3 (Cys l 12-Arg 158), and E4 (Arg l l2-Argl58) . In mixed w hite popula- tions, the all ele frequencies for E2, E3, and E4 are approx imately 0.08 , 0.77, and 0.15, respec- ti vely ^(l8l.

The 2 a llele is associated w ith tower LDL-C Ievels, and the 4 alle le is associated wi th hi gher levels relative to the 3 allele. Thi s observation Jed to the hypothesis th at apo E may play an important role in the develop ment of coronary heart disease. It has been estimated that carriers of the 4 allele have a 1.4-times-higher risk of developing co ronary hea rt disease than 3 car- riers

(l9l.

In the present study we speculated that APOE polymorphism can play a role espec ially

tigating these four candid ate genes in DCM patients. We hope our findin gs will enco urage in vestiga tors to des ign larger scale studies.

REFERENCES

l. Richardson P, McKenna W, Brisıow

M e

t al:

Report of

the I

995

WHO!ISFC Task Force

on

the Defiııiıioıı

and Classification of Card

iomyopathies. Circulation I

996; 93 : 84

1-2

2. Montgomery H, Keelinga PJ, Goldmana JH

, Humphri

- esb SE, Talmudb PJ, McKennaa WC: Lack of Associatio

n Between the Inscrtion{Deıeıion Poıymorphism

of the An- giotensin-Converting Enzyme Gene and Idiopathic Dilatcd Cardiomyopathy.

JACC ı

995;25:

ı

627-3

ı

3.

Tircı

L, Malle

t

C, Poirier O, et al: Lack of

associaıion

between polymorphisms of eight candidate genes and idio- pathic d

ilated

cardiomyopathy.

The CARDIGENE study JACC 2000; 35: 29-35

4. Charro

n P, Tesson

F, Poirier O et al: Identification of a gene

tic risk factor for idiopathic

dilatcd cardiomyopathy.

Iııvolvemenı

of a poly

morphism in the end

othclin

recepıor

type A gene. CARDIGEN E group. Eur Heart

J 1999;

20:

1587-91

5.

Rigaı

B, Hubc

rt C, Alhenc F, Cambien F, Corvol P, So-

ubrier F: An insertion /dele

tion polyınorphism

in

aııgioıcıı­

sin 1-converting enzyme gene accounting for half the vari-

ence of se

rum enzyme ıeveıs.

J C

l in lnvest 1990;86: 1343-

46

6.

Danser AHJ

, Schalekamp MADH, Box WA, e

t al: An-

giotensin-converıing

enzyme in

the human hearı. Effecı

of

the dclction/inscrıion poıymorphism. Circulaıion 1995;92:

ı387-88

7. Cambie

n

F, Pourier O,

Lecerf L, et

al: Delction poly-

morphism in the gene for angiotensin-convcrting enzymc

, ^is a potent risk fac

tor for

myocardial infarction. Nature

1992;259:64 ı

-4

8. Schunkert H, Hense HW, Holmer SR, et al: Association between a deletion polymorphyism of the angio tensin converting

enzyıne

gene and left ventricular hypertrophy.

N Eng J Med I 994;330: I 634-8

9. Marian AJ, Yu Q, Workman R, Greve G, Roberts R:

Angiotensin converting

enzyıne polyınorphyisın

in hypert- rophic

cardioınyopathy

and sudden cardiac death. Lancet 1993;342:

ı

085-6

10. Raynolds MY. Bristow MR, Bush EW, et al: Angio- tensin converting enzyme DO genotype in patients wi th ischemic or

idiopathic

dilatcd cardiomyopathy. Laneel 1993;342:

ı

073-5

ll. Sanderson JE,

Young YP, Yu CM, Chan S, Critchley

JAJH, Woo

KS: Lack of association between insertion/de-

letion

polyınorlıism

of the ang iotensin-converting

enzyıne

gene and end-stage

lıeart

failure due to ischemic or idio- pathic dilated cardiomyopathy in the Ch inese. Am J Cardi- ol 1996;77:

ı

008- 1 O

12. Asano K, Duteber OL, Port JD et al: Selective downre- g ulation of the angiotensin Il AT

1-receptor subtype in

fa

i- ling

human ventricular

nıyocardiuın.

Circulatio n 1997;95:

1193- 1200

H. Öz/ımı et al: Gene Polymoıplıisms in D ilared Cardiomyopatlıy

I 2. Tiret L, Bonn ardeaux X, Poirier O. et al: Syncrgistic effects of angiotensin-converting

enzyıne

and angiotensi n- II type I receptor gene

polyınorplıisıns

on risk of myocar- dia

l infarct

ion. Lancet I 994;344:9 1 0-3

14.

Marsden

PA, Heng HHQ, Scherer SW et al: Structurc and

chromosoınal localization of the h

uman constitutive endothelial nitric oxide synthase gene. J B io l

Cheın

1993;268: 17478-88

1 S. Balligand J and Cannon P: Nitric oxide synthases and cardiac

ınuscle.

Auloerine and paraerine influences. Arte- rioscler

Throınb

Vasc Bi ol 1997;17: I 846-58

16. Drexler H, Hayoz H, Munzel T, Just H, Zelis R, Brun- ner H: Endothelial function in congestive hea rt failu re. Am Heart J 1996; 126:761 -4

17. Curtiss LK, Boisverı

WA: Apolipoprote in E and athe- rosclerosis. Curr Opin Lipidol 2000; l

l :243-S 1

18. O'Brien KD, Deeb SS

, Ferguson M et al: Apolipopro- tein E localized in human coronary atherosclerotic plaques by in situ hy bridization and

iınınunohistocheınistry

and compar

ison

with

lipoprote

in

lipase.

Am J Pathol

1994;

144:538-48

19. Davignon J

, Gregg RE , Sing SF: Apol ipoprotein E

polyınorphisın

and atherosclerosis. Arteriosclerosis

1988;8:1-21