Introduction: Excessive alcohol consumption results in neuroadaptation, neurodegeneration, and differential expression of numerous genes.Objective: To determine the relationship between the expression of the alpha synuclein gene (SNCA) in blood, single nucleotide variant (SNV) in its promoter region, and chronic constipation in people with problems of alcohol consumption.Materials and methods: The sample consisted of 35 controls and 27 cases selected according to the score obtained with the AUDIT tool. This evidence concerns the gene SNCA and Chronic constipation.