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As a result, it is important to take a look at genetic disorders to get a feel for how they can impact a person and their risk of becoming a smoker. The following section will discuss a few of these common disorders, how they develop, and the different ways that they may cause a person to struggle with nicotine or other types of problematic addictions. Genetic Disorders Genetic disorders occur when there is a fault in a person’s DNA that triggers many types of health problems. Before delving into that further, it is important to examine chromosomes and their impact on DNA. A person’s strands of DNA are, as mentioned, made up of genes inherited from their parents. These genes combine to create a chromosome, which is a building block of DNA. Each person’s DNA should have forty-six chromosomes in twenty- three pairs—these all dictate every element of a person’s original biological makeup. For example, there is a height chromosome that is made up of genes from both parents. The dominant gene, as mentioned above, will prevail. So, if two short parents each pass a gene for a shorter height to their child, their height chromosome will keep the child short. However, the same thing can happen if two tall parents each have a short recessive gene that they pass to their child. While the exact genetic material a person gets from their parents is randomized during the fertilization process, the layout of the DNA is not. A chromosome in one person’s DNA also controls the same thing in another person’s. Take the twenty-third chromosomal pair as an example. This combination always dictates a person’s sex—a person who has two X chromosomes will be a girl, and a person with an X and a Y chromosome will be a boy. This uniformity helps to make genetics a very streamlined science.

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Understanding Genetics