As you might already know, a chromosome is nothing more than a collection of many different types of genes. And a gene is nothing more than a sequence of nucleotides that codes for some specific protein. Now, proteins are very important macromolecules. They're used by the cells of our body for many different types of processes and many different types of reactions. Now, there are many examples of different types of diseases that are a result of abnormalities that exist on either the genes of the chromosomes or the chromosomes themselves. So in this lecture, we're going to focus on a specific type of genetic disease, genetic disorder known as autosomal recessive disease.