Simply put, I got my DNA from my parents… half from mom and half from dad. They each copied half of their DNA for me, and their two half-copies were joined together to make my full copy. My full copy of DNA is my own personal instruction book1 that was used to build me, and still controls many things about me.
As I grew up, I made many copies of my instruction book. Today my body contains about 30 trillion copies of my unique DNA book.
When mom and dad copied their DNA for me, they undoubtedly made copy mistakes.2 According to recent estimates by some geneticists, my parents would have made about 100 uncorrected copy mistakes3 while copying their DNA for me. In addition to these new copy mistakes, mom and dad gave me additional copy mistakes that they inherited from their parents. Each generation adds to this accumulation of copy mistakes. Hence, my DNA contains thousands of accumulated copy mistakes.4 Such is the case for each person alive today; everyone is saddled with thousands of accumulated copy mistakes, most of which were inherited from their parents.
Occasionally a copy mistake will cause a noticeable genetic defect. Fortunately, most do not. Most copy mistakes are considered “nearly neutral” because they have a negligible effect on how a person is built or functions. However, even though most copy mistakes are nearly neutral, each one potentially chips away at the complex information in DNA (as would a minor typo in a very large book).5 Collectively, the complex information contained in human DNA appears to be gradually decaying6 from one generation to the next.
Creation Scientists and Evolution Scientists have different beliefs on the origin of DNA:
Evolution Scientists believe that our DNA began7 billions of years ago as a simple instruction book that very gradually became more and more complex during successive generations to become what it is today. This belief of increasing complexity does not appear to be consistent with the current study of DNA decay described above.
Creation Scientists, however, believe that human DNA was originally created extremely complex, and has been decaying gradually, but steadily ever since. This belief does appear to be consistent with the current study of DNA decay.8
References and notes for Chapter 7:
1. Geneticists sometimes refer to DNA as an instruction book. To understand why, see Chapter 6: How Does DNA Store Information?
2. Copy mistakes in DNA are called “mutations.”
3. There are about six billion “letters” in a complete set of human DNA, so 100 copy mistakes (mutations) would only change a very small fraction of the letters.
4. To see more on the number of new mutations per individual, as well as other information contained in this article, I recommend the book “Genetic Entropy” by John Sanford. Dr. Sanford was a Cornell University Professor for 25 years, and is a highly published geneticist, inventor, and the founder of two biotech companies. He has been granted more than 30 patents and is well-known in the genetics community as the principal inventor of the “gene gun” which is used in laboratories throughout the world to insert foreign DNA into cells.
5. Some geneticists believe there are sections of DNA that have “built-in redundancy” that allows some otherwise-significant mutations to be nearly neutral. Think of it as having a Plan A, a Plan B, a Plan C, and so on. Plan A is your best plan, but if it goes awry you proceed with Plan B (i.e. your second-best plan) and then Plan C, etc.
6. Natural selection can sometimes eliminate a mutation that has a significant effect, but it is useless against a mutation that is nearly neutral because the selection pressure against it would be much too small. And if it is correct that most mutations are nearly neutral, then most mutations cannot be eliminated by natural selection. Each of these “untouchable” mutations potentially adds to the generational decay of DNA.
Another reason natural selection may not be able to stop the generational decay of DNA is that there might be far too many mutations occurring for natural selection to keep up. Some geneticists estimate that each person is born with about 100 new mutations. Even if natural selection could eliminate most individuals in each generation, every reproducing survivor would spread dozens of new mutations into the population.
7. Evolution Scientists believe the first DNA book was that of the first bacterium, or perhaps some unknown organism that supposedly predated bacteria. They further believe that bacteria DNA evolved into our DNA, as well as the DNA of all other life.
8. Due to DNA decay, Creation Scientists believe we are less fit mentally and physically than our ancient ancestors. While it is true that technology continues to accumulate, that does not equate to increasing intelligence. If a human could somehow be born today with “ancient DNA,” Creation Scientists believe he/she would excel in many ways compared to peers.
Unlike Creation Scientists, some Evolution Scientists are surprised to learn of ingenious accomplishments made by ancient people, and even speculate that they must have had help from more advanced “aliens.”