Occasional smoking might eventually end in addiction. Currently, about 19% of adults around the world smoke tobacco. But, according to the WHO report, there is a global decline in tobacco use, especially among males. In India, according to the Global Adult Tobacco Survey (GATS) (2009-2010) and Global Adult Tobacco Survey (2016-2017) it has shown that there is a 3.3% decline in smoking rates (Fig 1). The global death rates have also declined from 146 per 100,000 people in 1990 to 90 per 100,000 in 2017.

Fig 1- GATS data for India comparing prevalence of smoking in the year 2016-17 and 2009-10
But have you ever wondered why certain people smoke and rest don’t? Addiction and susceptibility to smoking and tobacco intake, cessation and withdrawal symptoms are heritable and are associated with certain genes and genetic polymorphisms. The presence of certain genes leads to an increased risk of developing dependency and addiction towards smoking. This can be understood from the disparity in smoking prevalence and smoking behavior among various races and ethnic groups (Fig 2). There are genetic differences among populations, races, genders and even at an individual level. These differences can be . . .