Genes are the foundation of inheritance. They are passed down through the generations. They have DNA in them, which contains the instructions for building proteins. In cells, protein molecules would be doing the majority of the work. They transport molecules, build structures, destroy toxins, and perform a variety of other maintenance tasks. Single-gene disorders are one of three types of genetic disorders in which a mutation affects only one gene. One example is sickle cell anaemia. When chromosomes (or sections of chromosomes) are missing or changed, chromosomal diseases occur. Chromosomes are the structures that house our genes. Down syndrome is a chromosomal disorder. Complex disorders occur when there are mutations in two or more genes.
- Heart disease