Just as children may inherit normal features such as brown eyes or curly hair from one or both parents, children can also inherit certain disorders.
Genes are the units of hereditary material.
They contain coded instructions which direct the development of every cell and tissue in the human body. You might think of genes as blueprints, specifying how the body will develop and function. A gene is a stretch of DNA that tells a cell how to make a protein. Each amino acid is coded for by a three-letter sequence. The cell machinery reads this code, grabs the appropriate amino acids, and strings them together to make a protein.