Copilot answers the question, "What is junk DNA?"

The Microsoft browser (Edge) has a built in function called Copilot. It's an AI assistant based on ChatGPT-4.

I decided to test it byt asking "What is junk DNA?" and here's the answer it gave me.

Junk DNA, also known as non-functional DNA, refers to DNA sequences that lack any relevant biological function. Most organisms have some amount of junk DNA in their genomes, which primarily consists of pseudogenes and fragments of transposons and viruses. However, it’s possible that certain organisms may have substantial amounts of junk DNA (1).

Here are some key points about junk DNA:

• Definition: Junk DNA comprises regions of DNA that do not code for proteins and do not serve any known function.
• Composition: It includes pseudogenes (non-functional copies of genes), as well as remnants of transposons (mobile genetic elements) and viral DNA.
• Functional Elements: While protein-coding regions of genes are considered functional, other non-coding regions (such as those controlling gene expression, origins of replication, centromeres, and telomeres) are also considered functional.
• Controversy: Identifying functional versus non-functional DNA remains challenging. Some scientists use evolutionary criteria based on natural selection to determine functionality, while others interpret the data differently (1) (2).

The term “junk DNA” was coined by geneticist Susumu Ohno in 1972 to describe the noncoding sections of a genome, often composed of repeated segments scattered throughout the genome. These sections can arise through transposition, where DNA segments move to different positions within the genome2. Despite its name, junk DNA continues to be an area of scientific interest, and researchers are uncovering more about its potential roles and functions over time.

(1) Wikipedia: Junk DNA

(2) What is junk DNA, and what is it worth? by Wojciech Makalowski in Scientific American (2007)

This is a pretty good answer but that's not surprising since it's mostly based on the Wikipedia article that I created last year. :-)

I like the fact that Copilot gives us the source of its information and that it mentions the controversy. It's notable that it does not equate junk DNA with noncoding DNA in spite of the fact that this is the dominant definition on the internet. That suggests that Copilot is picking out more reliable sources in order to produce a better answer.

The bad news is that the reliable source is Wikipedia. In my field of expertise there is far too much misinformation in Wikipedia. We need to work hard to clean up Wikipedia if AI programs are going to use it.

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