Family Based Genetic Association Study of TLR4 Gene with Myocardial Infarction in Pakistan

Abstract

Introduction: TLR4-dependent pro-inflammatory signaling has been involved in the initiation, progression, and plaque destabilization phases of atherosclerosis which is the leading cause of MI. Aims & Objectives: To determine primarily the association of TLR4 gene with myocardial infarction through family clustering analysis as well as a case control association study. Secondarily to evaluate the environmental factors responsible for onset of MI (myocardial infarction) in Pakistani population. Place and duration of study: Current study was conducted at the Department of Zoology Government College University Lahore between 2019 and 2020. Material & Methods: Demographic information and blood samples were collected from various families with at least one or two family members affected with MI. DNA was isolated and targeted sequence was amplified by primer specific PCR reaction. Genotyping was achieved by Sanger sequencing. Results: The family clustering study found TT genotype of rs4986791 to be significantly associated with MI while other SNP (Asp299Gly; rs4986790) did not show any association with MI. In the case control association study, allele T was seen as a risk allele with significant association (p<0.05) of variants 4986791 to MI. Moreover, allele of rs 4986790 was found to be protective allele for participants. Smoking, air pollution, BMI, diabetes, positive family history and hypertension were found strongly responsible for development of MI. Conclusion: Results of this study indicate that SNP 1196C/T (Thr399Ile; rs4986791) in TLR4 gene is strongly associated with MI and other SNP rs4986790 was not associated with MI onset in a Pakistani family.

Keywords

• myocardial infarction, family clustering, case control association study, tlr (toll like receptor) 4 gene