Recent Advances on the Genetics of Spontaneous Coronary Artery Dissection.

Spontaneous coronary artery dissection (SCAD) has been acknowledged as a significant cause of acute myocardial infarction, predominantly in young to middle-aged women. SCAD often occurs in patients with fewer cardiovascular risk factors than atherosclerotic acute myocardial infarction. Unfortunately, SCAD remains underdiagnosed due to a lack of awareness among health care providers leading to misdiagnosis. The underlying pathophysiological mechanisms of SCAD are not well understood. SCAD occurring in members of the same family has been described, suggesting a potentially identifiable genetically triggered cause in at least some cases. However, thus far, the search for highly penetrant mutations in candidate pathways has had a low yield, often pointing to genes involved in other clinically undiagnosed hereditary syndromes manifesting as SCAD. Recent exploratory efforts using exome sequencing and genome-wide association studies have provided several interesting leads toward understanding the pathogenesis of SCAD. Here, we review recent publications where rare and common genetic factors were reported to associate with a predisposition to SCAD and indicate suggestions for the future strategies and approaches needed to fully address the genetic basis of this intriguing and atypical cause of acute myocardial infarction.

Genetic association study between T-786C NOS3 polymorphism and essential hypertension in an Algerian population of the Oran city.

BACKGROUND: Essential hypertension is an important risk factor for the development of cardiovascular disease. Important candidate genes such as NOS3 gene have been widely studied and reported to be associated with essential hypertension (HTN) in human populations. AIM: We aim in this study to analyze the relationship between NOS3 -786T/C, a common genetic variant and HTN in a sample of the Algerian population of the Oran city. METHODS: A case-control study has been performed in 154 subjects including 77 hypertensives and 77 normotensives. The recruitment of these subjects was done in local Health Centers of the city of Oran, West Algeria. HTN was defined as elevated systolic blood pressure SBD≥140  mmHg and or sustained diastolic blood pressure DBP≥90  mmHg, measured using an Omron® Automatic BP Monitor - M-3W machine. Consents were obtained from all participants. Polymerase chain reaction (PCR) combined with restrictive fragment length polymorphism (RFLP) was used to genotype the NOS -786T/C variant. RESULTS: The distribution of the allelic frequencies did not differ between cases and controls (OR = 1.48; 95%CI [0.94-2.32], P = 0.09). However, after adjustment with the age, sex, and body mass index, we observed significant association between NOS -786C allele and HTN status (OR = 2.08; 95%CI [1.18-3.66], P = 0.01). CONCLUSION: Our results indicate that the C allele of the NOS3 gene is associated with increased risk of essential hypertension in this sample of the Algerian population of the Oran city. Further validation in larger samples is needed to confirm this finding.

The relationship between MTHFR C677T gene polymorphism and essential hypertension in a sample of an Algerian population of Oran city.

BACKGROUND: Many studies have investigated the role of 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism in essential hypertension (EH), but with conflicting results. AIM: To determine the eventual association between 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism and hypertension in a sample of Algerian population from the Oran city. METHODS: A case-control study has been performed in 154 subjects including 82 hypertensives defined as subjects with elevated systolic blood pressure SBD≥140mmHg and or sustained diastolic blood pressure DBP≥90mmHg, and 72 normotensive subjects. Polymerase chain reaction (PCR) combined with restrictive fragment length polymorphism (RFLP) was used to detect the MTHFR C677T variant. RESULTS: We observe no significant differences between allelic and genotypic frequencies between cases and controls for C677T polymorphism (OR=1.51, 95% CI=0.89-2.56, P=0.13). Analyses adjusted for age, sex and body mass index improved the association level, though the association was still not significant (30% vs. 22%, OR=1.75, 95% CI=0.95-3.24, P=0.07). CONCLUSION: This work showed that genetic polymorphism related to the MTHFR gene (C677T) is not associated with the risk of hypertension in this sample of Algerian population. Larger case-control samples are required to clearly assess the role of this genetic variant in EH.