Lack of association between renin-angiotensin system (RAS) polymorphisms and hypertension in Tunisian type 2 diabetics.
BACKGROUND
The genes encoding renin-angiotensin system (RAS) components are potent candidate genes in both hypertension and diabetes namely ACE encoding the angiotensin converting enzyme and AGT encoding angiotensinogen. It has been suggested that the insertion/deletion (I/D) polymorphism in intron 16 of ACE gene is associated with ACE levels, and M235T gene polymorphism is associated with plasma AGT levels.


OBJECTIVE
We examined in this report the association between ACE I/D and AGT M235T polymorphisms with hypertension status in Tunisian type 2 diabetic subjects.


METHODS
Thirty nine hypertensive and 22 normotensive type 2 diabetic Tunisian patients were recruited for this study. The I/D polymorphism of ACE gene was analysed with nested PCR in order to avoid mistyping heterozygous individuals and the M235T polymorphism of AGT gene was analysed using PCR and allele specific restriction.


RESULTS
The distribution of DD, ID and II genotypes did not significantly differ between type 2 diabetic patients with or without hypertension (DD: 49%; ID: 41%; II: 10% vs DD: 36%; ID: 55%; II: 9%, respectively) (chi2=1.06, p=0.58). There was also no significant statistical difference between these two groups for the M235T polymorphism (TT: 20%; MT: 54%; MM: 26% vs TT: 27%; MT: 41%; MM: 32%, respectively) (chi2=0.95, p=0.62).


CONCLUSIONS
RAS polymorphisms do not seem to play a role in the development of hypertension in the studied Tunisian type 2 diabetic subjects.
Arfa
Imen
I
Molecular Investigation of Genetic Orphan Diseases Research Unit, Institut Pasteur de Tunis, Tunisia.
Nouira
Sonia
S
Abid
Abdelmajid
A
Bouafif-Ben Alaya
Nissaf
N
Zorgati
Mohamed Majdi
MM
Malouche
Dhafer
D
Manai
Imen
I
Ben Rayana
Mohamed Chiheb
MC
Blousa-Chabchoub
Samira
S
Ben Romdhane
Habiba
H
Ben Ammar
Mohammed Slim
MS
Ben Salah
Afif
A
Abdelhak
Sonia
S
D000368:Aged; D000465:Algorithms; D000808:Angiotensinogen / Q000235:genetics*; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D005260:Female; D006801:Humans; D006973:Hypertension / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012084:Renin-Angiotensin System / Q000235:genetics*; D014416:Tunisia
D000808:Angiotensinogen