Question

All of the following statements about gene therapy are true except: a. It can successfully treat SCID. b. Retroviruses insert their genetic material randomly. c. Its purpose is to modify embryos according to the parents" wishes. d. It may soon be able to treat cancer.

Short answer

C

Step-by-step solution

- Understand the Question

We need to determine which statement about gene therapy is false. The options provided are descriptions of gene therapy applications and characteristics.

- Evaluate Option A

Statement A says gene therapy can successfully treat SCID (Severe Combined Immunodeficiency). This is true, as gene therapy has been used to treat SCID by inserting a normal gene to replace the defective one.

- Evaluate Option B

Statement B mentions that retroviruses insert their genetic material randomly. This is also true; retroviruses can integrate their genetic material into the host genome at random locations, which can sometimes cause problems.

- Evaluate Option C

Statement C claims gene therapy's purpose is to modify embryos according to the parents' wishes. This is false. The primary goal of gene therapy is to treat or prevent diseases, not to modify embryos for desired traits.

- Evaluate Option D

Statement D suggests that gene therapy may soon be able to treat cancer. This is true as ongoing research aims to use gene therapy techniques in cancer treatment.

- Identify the Incorrect Statement

After evaluating all the options, we conclude that statement C is incorrect.

Key concepts

Retroviruses

Retroviruses are a type of virus that inserts a copy of their genetic material into the DNA of a host cell during replication. This process is done randomly, which can sometimes lead to unintended consequences, such as disrupting important genes or activating harmful ones. Retroviruses are used in gene therapy because they have a natural ability to deliver genetic material into cells. They serve as vectors, or carriers, that transport therapeutic genes to target cells. Although this random insertion can be problematic, scientists are working to improve the precision and safety of retroviral gene delivery.

SCID Treatment

Severe Combined Immunodeficiency (SCID) is a genetic disorder that impairs the function of the immune system, making individuals extremely susceptible to infections. Gene therapy has been highly successful in treating SCID by introducing a normal copy of the defective gene into the patient's stem cells. These corrected stem cells can then develop into a healthy, fully functioning immune system. This approach has provided many SCID patients with a long-lasting cure, allowing them to live healthier lives.
Some key points about SCID gene therapy include:

• It involves the use of viral vectors to deliver the normal gene.
• Stem cells are usually taken from the bone marrow of the patient.
• After gene therapy, patients often exhibit a significant improvement in immune function.

Cancer Treatment

Gene therapy holds great promise for treating various types of cancer. The goal is to correct or modify the genes within cancer cells to slow down or stop tumor growth. Researchers are exploring several strategies:

• **Introducing genes that promote the death of cancer cells.**
• **Enhancing the immune system's ability to attack cancer cells.**
• **Inserting genes that make cancer cells more sensitive to other treatments like chemotherapy.**

Although these treatments are still largely experimental, early results are promising, suggesting that gene therapy could become an important weapon in the fight against cancer.

Genetic Modification Ethics

The ethics of genetic modification, especially in humans, is a hotly debated topic. The primary ethical concerns include:

• **Safety Risks:** The unpredictability of gene insertion raises concerns about unintended genetic changes and potential long-term effects.
• **Equity:** There is a risk that gene therapy could be expensive, making it accessible only to the wealthy, thereby increasing social inequality.
• **Consent:** When it comes to modifying embryos, there is the ethical dilemma of consent, as future generations cannot consent to genetic modifications made before they are born.
• **Purpose:** Using gene therapy to treat or prevent diseases is generally considered ethical, but using it for non-medical enhancements, such as altering physical appearance or abilities, raises significant ethical questions.

As the field advances, ongoing ethical dialogue will be crucial in guiding the responsible use of genetic modification technologies.