DNA Detective: How God’s Design Helps Solve Mysteries

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You have your very own nose shape, maybe some freckles in places no one else has them, and fingerprints that belong only to you. Your ears have their own special shape, and even the way you write your name is different from everyone else! You are fearfully and wonderfully made!

Unzipping the Secrets of DNA

But here’s the coolest part: God created you with something microscopic inside you that proves you are totally unique. It’s called DNA, and forensic scientists (they’re like detectives) use it to identify people just like they use fingerprints. Your DNA is like a secret code that makes you YOU, and no one else in the entire world has the same code.1 How amazing is that?

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A Hair, a Clue, and DNA Too

DNA evidence is a helpful clue to solve mysteries. DNA is found in blood, spit (saliva), roots of hair (not the hair itself), skin cells, bone marrow (squishy stuff inside bones), and more. Forensic investigators are trained to look for these tiny clues. Because DNA evidence is so delicate, it must be collected carefully, packaged in special containers, and transported safely to a lab for analysis.

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In the lab, scientists extract (or remove) it from the evidence. This requires fancy equipment and special training. Scientists make millions of copies of the DNA using a process called amplification (say it: am-plih-fih-KAY-shun). Amplification is like taking a tiny instruction book and making millions of photocopies. Having lots of copies allows the scientists to run multiple tests and to create a sample large enough to create a DNA fingerprint of a person.

The Amazing Race: How DNA “Runs”!

Scientists have a cool way to look at DNA called electrophoresis (say it: ee-lek-tro-for-EE-sis). It’s kind of like a race where tiny pieces of DNA run through a messy, spongy obstacle course. Imagine running through a giant sponge with your friends. Some of you are small and zip right through the holes. Others are bigger and get slowed down. That’s exactly what happens to DNA!

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The DNA Race

1. The racers (DNA samples) get ready: The samples of DNA from the crime scene evidence are cut into different size pieces. Some are short, some are medium, and others long. Each person’s DNA will be cut at different places.
2. Line up at the starting line: The DNA fragments are piped into holes at one end of a gel. These holes are called wells.
3. Ready, set, go! (turn on the electric current): DNA is negatively charged. When a battery is attached to the gel box, the positive terminal is at the opposite end of the wells. The positive charge pulls the negatively charged pieces of DNA to the opposite end, just like a magnet!
4. The obstacle course (running through the gel): Along the race path, the DNA will have to squeeze through tiny, tangled pores (holes) in the gel. Small pieces will have an easier time getting through the pores while large pieces get stuck.
5. The finish line (making the fingerprint): When the DNA has finished the race, the pieces have been separated by size from longest to shortest. The pieces appear as bands or stripes in the gel. The pattern of the bands is like a barcode that belongs only to you. This is called the DNA fingerprint.

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What Happens Next?

The DNA fingerprint is then entered into CODIS (Combined DNA Index System). This helps forensic investigators match DNA from a crime scene with DNA from millions of people to solve mysteries and catch bad guys! But DNA fingerprinting also helps to prove innocence of someone who has been falsely accused.

God is a God of truth and justice. Psalm 89:14 tells us, “Righteousness and justice are the foundation of your throne; steadfast love and faithfulness go before you.” DNA fingerprinting is one of the tools scientists use to bring justice into this sin-cursed world.

Do you have a question about forensics or how forensic scientists pursue God’s desire for justice? Ask your parents to help you submit your question today!

Footnotes

1. Parents, check out Dr. Rivera’s book for kids DNA, God, & You! here: https://answersingenesis.org/store/product/dna-god-you.