Biochemical genetics is a combination of biochemistry and genetics. Biochemistry deals largely with the structure and function of cellular components, such as proteins, carbohydrates, lipids, nucleic acids, and other biomolecules, and of their functions and transformations during life processes. Genetics is a basically a study in heredity, particularly the mechanisms of hereditary transmission, and the variation of inherited characteristics among similar or related organisms. Some of the branches of genetics include biochemical genetics, cytogenetics, developmental genetics, genetic engineering, etc. Thus, biochemical genetics is a branch of genetics that deals with the chemical structure of the genes and with the mechanisms by which the genes control and regulate the structure and synthesis of proteins. It studies the relationship of genes and their control over the function of enzymes in biochemical pathways. It is genetics in terms of the chemical (biochemical) events involved, as in the manner in which DNA molecules replicate and control the synthesis of specific enzymes by the genetic code.