Scale: 5 nm

Genes are sequences of DNA that, for the most part, code for proteins. The flow of genetic information from DNA to RNA to protein has been referred to as the central dogma of molecular biology.

Mutations in genes can affect the resulting proteins and some mutations cause disease. To treat genetic diseases, scientists and doctors can intervene at different steps in the central dogma.

Scroll down to explore the steps in the central dogma pathway in a human cell. Click on the plus signs to explore a genetic medicine strategy that is being used to intervene at a particular step and a disease that could be treated using that strategy.


Most cells in our bodies contain DNA inside the nucleus.

This image is a round semi-translucent shape labeled cytoplasm, with a cut-away in the front revealing internal cell structures of varying shapes, including a central round structure labeled nucleus. There is a cut-away in the front of the nucleus revealing an internal nested and coiled spaghetti-like chain labeled D N A.


The DNA in the nucleus of a cell is referred to as its genome. The human genome contains about 20,000 genes.

This image depicts coiled strands of D N A. The D N A consists of two parallel strands twisted in the shape of a helix.