en Genetics Original Article Original Article <span style="font-size:14px;"><span style="font-family:Times New Roman;"><span style="line-height:14pt"><b><i><span style="color:blue">Background</span></i></b><i><span style="color:blue">:</span></i> The <i>MUC1</i> gene encodes glycoproteins attached to cell membrane that play a protective role in gastric cancer and protect epithelial surfaces against external factors such as<i> Helicobacter pylori</i>. <i>H. pylori </i>infection can induce a cascade of innate and acquired immune responses in gastric mucosa. Relationship between rs4072037G>A polymorphism of <i>MUC1</i> gene and increased susceptibility to <i>H. pylori </i>infection aimed to investigate in patients with gastric cancer in Mazandaran, northern Iran.</span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Methods:</span></i></b> A case-control study was conducted on 99 patients with gastric cancer (<i>H. pylori </i>positive and negative) and 98 controls (<i>H. pylori </i>positive and negative) without gastric cancer (confirmed by pathological biopsy samples obtained during endoscopy). <i>H. pylori</i> infection was diagnosed by histological examination using Giemsa staining. Genomic DNA extracted from peripheral blood was analyzed by PCR-RFLP technique.<span style="font-size:10.0pt"></span></span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Results:</span></i></b> Analysis of all genetic models showed no significant relationship between rs4072037G>A polymorphism and risk of gastric cancer (GC). The relationship between <i>H. pylori </i>infection and rs4072037G>A polymorphism showed an increased susceptibility to gastric cancer in both positive and negative <i>H. pylori </i>groups (including case and control groups). The genetic model of GA/GG and <i>H. pylori</i>- positive versus GA/GG and <i>H. pylori</i>-negative showed a significantly increased susceptibility to gastric cancer (OR=0.251, CI: 0.128-0.493, P=0.000).<span style="font-size:10.0pt"></span></span><br> <span style="line-height:14pt"><b><i><span style="color:blue">Conclusion</span></i></b><i><span style="color:blue">:</span></i> These findings indicate that rs4072037G>A polymorphism may interact with <i>H. pylori </i>infection to increase the risk of GC.<span style="font-size:10.0pt"></span></span></span></span> Gastric Cancer, H. pylori, MUC1 5640G>,,A polymorphism, PCR-RFLP, Genotype 132 140 http://caspjim.com/browse.php?a_code=A-10-2915-1&slc_lang=en&sid=1 Ramin Shekarriz raminshf@gmail.com 100319475328460046555 100319475328460046555 Yes Department of Hematology and Oncology, Gastrointestinal Cancer Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Hadi Jabbari dr.hadi.jabbari.hj@gmail.com 100319475328460046556 100319475328460046556 No Department of Hematology and Oncology, Gastrointestinal Cancer Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Reza Alikhani alikhani.d@gmail.com 100319475328460046557 100319475328460046557 No Department of Hematology and Oncology, Gastrointestinal Cancer Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Reza Alizadeh-Navaei reza_nava@yahoo.com 100319475328460046558 100319475328460046558 No Department of Hematology and Oncology, Gastrointestinal Cancer Research Center, Mazandaran University of Medical Sciences, Sari, Iran. Mohammad Bagher Hashemi‑Soteh hashemisoteh@gmail.com 100319475328460046559 100319475328460046559 No Immunogenetics Research Center, Cell and Molecular Research Center, Faculty of Medicine, Mazandaran University of Medical Sciences, Sari, Iran