Problem 5 - Campbell Biology

Question

Level 1: Knowledge/Comprehension DNA technology has many medical applications. Which of the following is not done routinely at present? (A) production of hormones for treating diabetes and dwarfism (B) analysis of gene expression for more informed cancer treatments (C) gene editing by the CRISPR-Cas9 system in viable human embryos to correct genetic diseases (D) prenatal identification of genetic disease alleles

Step-by-Step Solution

Answer

Option C is not done routinely.

Step 1: Understand the Question

Identify what the question is asking. It asks which DNA technology application is not done routinely at present.

Step 2: Evaluate Option A

Consider if the production of hormones for treating diabetes and dwarfism is done routinely. Insulin (for diabetes) and growth hormones (for dwarfism) are commonly produced using DNA technology.

Step 3: Evaluate Option B

Consider if the analysis of gene expression for more informed cancer treatments is done routinely. Gene expression analysis is a routine process in cancer research and treatment.

Step 4: Evaluate Option C

Consider if gene editing by the CRISPR-Cas9 system in viable human embryos is done routinely. Gene editing in viable human embryos is highly controversial and generally not performed routinely due to ethical and safety concerns.

Step 5: Evaluate Option D

Consider if prenatal identification of genetic disease alleles is done routinely. Prenatal genetic testing is common for identifying potential genetic disorders early.

Step 6: Determine the Correct Answer

Identify which option is not done routinely based on the evaluations made in the previous steps. Option C is the correct answer as it involves practices not routinely performed due to ethical and safety reasons.

Key Concepts

Gene Expression Analysis

Gene expression analysis is a powerful tool used in modern medicine to understand the activity of genes in different cell types. By analyzing which genes are turned 'on' or 'off,' doctors can better diagnose and treat diseases, especially cancer.

• Helps identify which genes are involved in specific types of cancer.
• Allows for personalized treatment plans based on a patient's unique genetic profile.
• Used for monitoring the effectiveness of ongoing treatments.

This technology involves extracting RNA from a sample, converting it to cDNA, and then using tools like microarrays or sequencing to measure gene expression levels. Such insights help in making treatment decisions, such as whether a patient might respond better to chemotherapy or immunotherapy.

CRISPR-Cas9 Gene Editing

CRISPR-Cas9 is a revolutionary technology that allows precise editing of the genome.

• Involves 'cutting' DNA at specific locations to add, remove, or alter genetic material.
• Has potential applications in treating genetic disorders by correcting faulty genes.
• Currently, its use in viable human embryos is limited due to ethical and safety concerns.

The technology works by using a guide RNA to find the specific DNA sequence and the Cas9 enzyme to make cuts at these locations. Although promising, its application in human embryos for germline editing is still under strict regulation due to potential long-term effects.

Hormone Production Using DNA Technology

DNA technology has made it possible to produce important hormones for medical use.

• Insulin, used to treat diabetes, is commonly produced using genetically engineered bacteria.
• Human growth hormone, used to treat growth disorders, is also produced using recombinant DNA technology.

These medical advances involve inserting the human gene responsible for the hormone into bacterial DNA. The bacteria then produce the hormone in large quantities, which can be purified and used for treatment. This method is highly efficient and has significantly improved the availability of these hormones.

Prenatal Genetic Testing

Prenatal genetic testing allows doctors to detect genetic abnormalities in a fetus early in pregnancy.

• Commonly tests for diseases like Down syndrome, cystic fibrosis, and other inherited conditions.
• Can be done through procedures like amniocentesis and chorionic villus sampling (CVS).

These tests analyze the DNA from the fetus to look for specific mutations or chromosomal abnormalities. Early detection allows parents and healthcare providers to prepare for and manage any potential health issues, ensuring better care for the baby.