Gene Networks Are Intolerant of Mutation | The Institute for Creation Research

Gene Networks Are Intolerant of Mutation

Fish supposedly evolved into people by gene mutations, but a recent report shows that mutations have disastrous effects.1 Not only are individual genes essential, but when they are inhibited, entire gene networks are disrupted, resulting in severe growth and development problems in the organism.

One of the main model organisms used to study gene and genome function is the small soil worm called a nematode. Nematodes are the most abundant type of animal on earth and live in many different environments. They also make excellent test animals for genetic study in the lab because they are easy to raise, have a small genome size, and much is known about their biology.

In the past, scientists used a variety of technologies to sequentially inhibit individual genes in the nematode genome.2, 3 Their goal was to ascertain which genes are essential to its survival. However, in these early studies, researchers only analyzed the effects of gene mutation by looking at individual nematodes for observable changes. They also only evaluated the effects of mutation on a single generation. Therefore, they missed detecting the results of disabling genes where the effects were subtle.

In this recent study, scientists observed the effects of 550 sequentially inhibited genes on the overall fitness of nematodes over eight generations. Fitness is the ability of a population of organisms to grow and reproduce over time compared to a control population that does not have the mutation. Fitness can also be tested in different environments that apply various stresses.

In the majority of cases, the disruption of single genes reduced the fitness of the nematode populations. This was an effect that kept increasing with successive generations. Theoretically, this would have eventually led to extinction.

As a result, researchers concluded that most every gene tested was essential to survival of the nematode. Because the mutant worms' fitness decreased over successive generations, the researchers also concluded that even single mutations negatively impact entire gene networks.

The researchers wrote,

In contrast to previous estimates, we find that, in these multigeneration population assays, the majority of genes affect fitness, and this suggests that genetic networks are not robust to mutation. Our results demonstrate that, in a single environmental condition, most animal genes play essential roles.1

In the biological evolution model, the process of genome mutation not only involves the hypothetical alteration of gene sequences, but the idea that not all genes are essential to life. In other words, there is room in the cell system for DNA to randomly change, so that once in a while it can spit out some useful new gene sequence to advance evolutionary progress. However, this new study shows that even though the cell systems in roundworms are dynamic and environmentally responsive, the fine-tuned DNA-based informational system that underlies it cannot be corrupted without diminishing its ability to survive.

So in addition to refuting evolution, nematode gene networks show every sign of carefully crafted system engineering.

References

  1. Ramani, A. K. et al. 2012. The Majority of Animal Genes Are Required for Wild-Type Fitness. Cell. 148 (4): 792-802.
  2. Kamath, R. L. et al. 2003. Systematic Functional Analysis of the Caenorhabditis elegans Genome Using RNAi. Nature. 421 (6920): 231-237.
  3. Sonnichsen, B. et al. 2005. Full-Genome RNAi Profiling of Early Embryogenesis in Caenorhabditis elegans. Nature. 434 (7032): 462-469.

* Dr. Tomkins is Research Associate at the Institute for Creation Research and received his Ph.D. in Genetics from Clemson University.

Article posted on December 17, 2012.

The Latest
NEWS
"100-Million-Year-Old" Bacteria?
Researchers from the Japan Agency for Marine-Earth Science and Technology have recovered what they claim are 100-million-year-old microbes. Drilling 74.5...

NEWS
Origin of Tectonic Plates Best Explained by the Flood
A new study published in Nature Communications claims to have figured out how the tectonic plates may have originated.1 It’s been over...

NEWS
Give Today and Support Biblical Creation Ministry
North Texas Giving Day is here once again! Will you help us reach the next generation? Your generosity will empower ICR and our Dallas Museum—the...

NEWS
Mammalian Brains Prove Evolutionary Disconnect
The evolutionary model of brain development predicted that the complexity of neural connectivity should have increased as brains became larger and the...

NEWS
North Texas Giving Day Next Week!
North Texas Giving Day is almost here! Will you help us reach the next generation? Your generosity will empower ICR and the ICR Discovery Center for Science...

NEWS
Celebrating One Year at the ICR Discovery Center
Thank you to all who joined us for the ICR Discovery Center for Science & Earth History’s First Anniversary Celebration! ICR staff enjoyed meeting...

NEWS
New Evidence Hurts Feathered Dinosaur Theory
Is a dinosaur still a dinosaur if it has flight feathers? A new study points to some fascinating evidence that contradicts the idea of feathered dinosaurs...

NEWS
New Planetarium Show: Exploring Deep Space
The ICR Discovery Center for Science & Earth History is celebrating its first anniversary since the Grand Opening on September 2, 2019. To commemorate...

NEWS
Inside September 2020 Acts & Facts
What's the story behind ICR's new President? What milestone are we celebrating this month at the ICR Discovery Center? How do comets affirm...

NEWS
Sunflower Heliotropism: August Sunlight for Making Tons of Seeds
August is an important month for sunflowers—those gigantic, bright-yellow flowers with brownish, round seed heads bordered by radiating yellow ligules...