In this module you will cover:

The control of gene expression: Cells regulate their activity by controlling the processes of transcription and translation. Although all cells in an organism contain the same DNA, they do not express all of their genes. Instead, they express only the genes necessary for their specific function. This selective gene expression enables cells to become specialised, forming different tissues and organs in multicellular organisms.

Modern understanding shows that gene expression is more complex than once thought. The role of epigenetic regulation — chemical modifications to DNA and histones that affect transcription without changing the DNA sequence — is now seen as a key mechanism in gene control.

Gene technologies: Humans are also learning how to manipulate gene expression deliberately. By modifying the epigenome, or altering the genome and proteome of cells, scientists are developing powerful medical and biotechnological tools. These include:

• Diagnosing genetic disorders.
• Developing gene-based therapies.
• Producing useful proteins in biotechnology.

Understanding how cells control gene expression helps explain how diseases can develop when these systems go wrong. 

This knowledge also forms the foundation for using DNA technologies in medicine, allowing for precise diagnosis, targeted treatments, and even personalised medicine.