Gene Therapy and Genetic Screening

This lesson covers gene therapy — the treatment of genetic disorders by introducing functional genes — and genetic screening — testing individuals for specific genetic conditions. Both topics are required by the Edexcel A-Level Biology specification (9BI0, Topic 7).

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What Is Gene Therapy?

Gene therapy is the introduction of a functional copy of a gene into the cells of a patient to treat or prevent a genetic disorder. The aim is to compensate for a faulty or missing gene by providing a working version.

Gene therapy targets disorders caused by single gene defects (monogenic disorders), such as:

• Cystic fibrosis (CFTR gene)
• Severe combined immunodeficiency (SCID) — the ADA gene
• Sickle cell anaemia (HBB gene)
• Huntington's disease (HTT gene) — more challenging

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Types of Gene Therapy

Somatic Cell Gene Therapy