Belkahla R, Omezzine A, Kchok K, Rebhi L, Ben Hadj Mbarek I, Rejeb J, Ben Rejeb N, Slimane N, Nabli N, Ben Abdelaziz A, Boughzala E, Bouslama A
UR MSP 04/28, service de biochimie, hôpital universitaire Sahloul, route Ceinture, cité Sahloul, 4054 Sousse, Tunisie.
Ann Cardiol Angeiol (Paris). 2008 Aug;57(4):219-24. doi: 10.1016/j.ancard.2008.05.018. Epub 2008 Jul 1.
Hyperhomocysteinemia is known as an independent-risk factor for coronary-artery disease (CAD). However, the effect of homocystein metabolic enzymes polymorphisms on CAD is still controversed. We investigated the relation between homocystein metabolic key enzymes polymorphisms, homocystenemia and coronary stenosis in a Tunisian population.
Samples were collected from 251 CAD patients documented by angiography. Genotyping were performed for C677T methylene-tetrahydrofolate reductase (MTHFR), A2756G methionine-synthase (MS) and 844ins 68 cystathionine-beta-synthase (CBS). We measured fasting plasma tHcy, folate and vitamin B12.
There was significant increase in homocysteinemia for homozygous genotypes of C677T MTHFR (p<0.001) and A2756G MS (p=0.01), but not for 844ins68 CBS (p=0.105). Potential confounders adjusted odds-ratios for significant coronary stenosis, associated with MTHFR TT, MS GG and CBS insertion, were respectively 1.78 (p=0.041); 2.33 (p=0.036) and 0.87 (p=0.823). The effect of mutated MTHFR genotype was more pronounced on homocysteinemia (21.4+/-9.1 micromol/L; p<0.001) and coronary stenosis (OR=2.73; p=0.033) at low folatemia (< or =6.1 ng/mL).
MTHFR TT and MS GG genotypes increase tHcy concentration and coronary stenosis risk, especially with low folatemia.
高同型半胱氨酸血症是冠状动脉疾病（CAD）的独立危险因素。然而，同型半胱氨酸代谢酶多态性对CAD的影响仍存在争议。我们在突尼斯人群中研究了同型半胱氨酸代谢关键酶多态性、高同型半胱氨酸血症与冠状动脉狭窄之间的关系。
从251例经血管造影证实的CAD患者中采集样本。对C677T亚甲基四氢叶酸还原酶（MTHFR）、A2756G甲硫氨酸合成酶（MS）和844ins 68胱硫醚-β-合成酶（CBS）进行基因分型。我们测量了空腹血浆总同型半胱氨酸（tHcy）、叶酸和维生素B12。
C677T MTHFR（p<0.001）和A2756G MS（p=0.01）的纯合基因型患者的同型半胱氨酸血症显著增加，但844ins68 CBS患者未增加（p=0.105）。与MTHFR TT、MS GG和CBS插入相关的显著冠状动脉狭窄的潜在混杂因素调整比值比分别为1.78（p=0.041）；2.33（p=0.036）和0.87（p=0.823）。在低叶酸血症（≤6.1 ng/mL）时，突变的MTHFR基因型对同型半胱氨酸血症（21.4±9.1 μmol/L；p<0.001）和冠状动脉狭窄（OR=2.73；p=0.033）的影响更为明显。
MTHFR TT和MS GG基因型会增加tHcy浓度和冠状动脉狭窄风险，尤其是在低叶酸血症时。
