Source: blogs.plos.org Author: Catherine Chang et al. Turning red after consuming alcohol may seem like a mere social inconvenience. Yet, behind this red complexion lies a far more serious problem. ALDH2 deficiency, more commonly known as Alcohol Flushing Syndrome or Asian Glow, is a genetic condition that interferes with the metabolism of alcohol. As a result, people with ALDH2 deficiency have increased risks of developing esophageal and head and neck cancers . Globally, this deficiency affects 540 million people — 8% of the world population. In East Asia (which includes Japan, China, and Korea), this is a much bigger problem, where 36% of the population is affected [1]. In our home, Taiwan, approximately 47% of the population carries this genetic mutation — the highest percentage in the world [2]! Normally, ethanol is first converted to acetaldehyde (a toxic intermediate) by the enzyme alcohol dehydrogenase (ADH). A second enzyme, aldehyde dehydrogenase 2 (ALDH2), then converts toxic acetaldehyde into acetate, a compound which can be safely metabolized in the body. For people who carry wild type ALDH2*1, acetaldehyde can be broken down quickly. People with ALDH2 deficiency, however, have a point mutation which leads to the less efficient mutant ALDH2*2 [3], [4]. Enzymatic activity in ALDH2-deficient individuals can be as low as 4% compared to wild type [4], [5], [6], [7]. As a result, acetaldehyde accumulates and induces an inflammatory response that causes the skin to flush after drinking alcohol [8]. Turning red is the most obvious result of ALDH2 deficiency, but [...]