Single-gene genetic disorders, also referred to as monogenic or Mendelian, occur when genetic mutations occur in the DNA sequence of a single gene. Genes perform a variety of functions, such as performing most life function, code for proteins, make up most of all cellular structures, and carry out most of the work. When a gene becomes mutated, a disorder can result due to its protein not being able to carry out the normal functions that it should. These mutations affect approximately every one out of every two-hundred births and there are over 6,000 single-gene disorders. Some examples include sickle cell anemia, Huntington's disease, cystic fibrosis, Marfan syndrome, and hereditary hemochromotosis. These are inherited in recognizable patterns, including autosomal recessive, autosomal dominant, and X-linked.
