Gene Editing Simplified: Four Key Steps

To envision a straightforward method for gene editing aimed at enhancing intelligence, we can break it down into four essential steps:

1. Identify specific DNA sequences to modify.
2. Create a tailored molecule to execute these changes.
3. Deliver the custom molecule to the necessary cells.
4. Validate the results and monitor for side effects.

If you guessed that we can currently accomplish just one of these steps, you’re right! While we can design custom molecules, the other components remain complex and challenging.

CRISPR, short for “Clustered Regularly Interspaced Short Palindromic Repeats,” refers to a protein, Cas9, that utilizes a short DNA sequence to locate and cut DNA strands at targeted locations. Though our cells are equipped to repair these cuts, sometimes the repairs can lead to unintended changes.

Despite its effectiveness, CRISPR is not without hurdles. Identifying which genes to modify is a significant challenge due to the sheer size of the human genome, which consists of approximately 3.2 billion base pairs. Although human genomes are largely similar, they can differ by 4-5 million bases, accounting for about 0.1% of genetic variation.

Understanding these variations is crucial, as it remains unclear how many of them influence intelligence. Importantly, intelligence is not dictated by a single gene but is the result of complex interactions among millions of genetic factors and environmental influences.

The Complexity of Genetic Traits

Imagine flipping a coin 12,000 times, where each "heads" results in a small increase in height, and each "tails" a decrease. Even with the potential to convert a few "tails" to "heads," the impact on height would be negligible due to the multitude of factors involved.

In our current understanding, CRISPR can facilitate some targeted modifications, but the vast number of genetic locations and their minor contributions make significant enhancements challenging.

Reaching Our Genetic Targets

CRISPR operates on DNA, but delivering it effectively to all cells in the body remains a significant limitation. Presently, CRISPR therapies involve extracting cells, editing them in a lab, and reinserting them, which works well for certain cell types but is impractical for many others.

The most viable time to edit genes is during the embryonic stage, where changes could propagate through all cells as the embryo develops. However, this approach raises ethical concerns and is limited to creating smarter offspring rather than enhancing existing individuals.

The Risks of Gene Editing

While CRISPR boasts impressive accuracy, it is not infallible. A margin for error exists, and unintended cuts can have serious consequences, including potential cancer development. Monitoring cells during laboratory editing is feasible, but in vivo modifications pose greater risks, as there is no way to reverse them.

Could Designer Babies Be a Reality?

Returning to the initial question, can gene editing make someone smarter? Currently, the answer is no. The lack of understanding regarding which genes to modify, combined with the necessity for in vitro fertilization, makes this impractical.

For those seeking smarter or taller children, the most effective methods available today are:

1. Financial Investment: Wealthier families often provide better educational opportunities, which can enhance intelligence.
2. Selecting Donors: Choosing sperm or egg donors with desirable traits can influence the genetic makeup of offspring.

At this juncture, our understanding of genetics does not allow for targeted modifications to enhance intelligence. Instead, focusing on improving environmental conditions remains the most effective approach to foster intelligence.