Lack of association betweenFokIpolymorphism in vitamin D receptor gene (VDR) & type 2 diabetes mellitus in the Tunisian population.
OBJECTIVE
The impact of several environmental and genetic factors on diabetes is well documented. Though the association between the vitamin D receptor (VDR) gene polymorphisms and type 2 diabetes mellitus (T2DM) has been analyzed in different ethnic groups, the results have been inconsistent. The aim of this study was to evaluate the possible association between VDR FokI polymorphism and genetic susceptibility to T2DM in Tunisian population.


METHODS
A total of 439 unrelated patients with T2DM and 302 healthy controls were included in the study. Genomic DNA was extracted from blood and genotyped for the single nucleotide polymorphism (SNP) of FokI (T/C: (rs2228570) by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis.


RESULTS
The genotype distribution and the relative allelic frequencies for the FokI polymorphism were not significantly different between T2DM and controls: in T2DM patients the frequencies of the CC, CT, and TT genotypes were 52.6, 41.0, and 6.1 per cent, respectively, and in controls the genotype frequencies were 55.6, 38.7, and 5.6 per cent, respectively. In our study, the TT genotype of the FokI polymorphism was not associated with T2DM (OR =1.19, 95% CI 0.63 - 2.25, P=0.577).


CONCLUSIONS
Our study showed no significant association of the FokI polymorphism in the vitamin D receptor gene with type 2 diabetes mellitus in Tunisian population.
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Imen
I
Mahjoubi
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Amani
A
Kallel
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Mohamed Hédi
MH
Sbaï
Endocrinology Department, Rabta University Hospital, Tunis, Tunisia.
Bochra
B
Ftouhi
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Meriam
M
Ben Halima
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Zeineb
Z
Jemaa
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Moncef
M
Feki
Endocrinology Department, Rabta University Hospital, Tunis, Tunisia.
Hedia
H
Slimane
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Riadh
R
Jemaa
Research Laboratory LR99ES11, Biochemistry Department, University of Tunis El Manar, Tunis, Tunisia.
Naziha
N
Kaabachi
D000328:Adult; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics* / Q000473:pathology; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D018167:Receptors, Calcitriol / Q000235:genetics*; D014416:Tunisia
D018167:Receptors, Calcitriol; C579457:VDR protein, human