Functionally unconstrained DNA is not conserved
As different species evolve, their DNA segments are preserved only if they contribute to the organism’s fitness. DNA segments that are not functionally constrained should mutate and diverge over time. The result is that similar yet functionally unconstrained DNA segments should not be found in distant species. The corollary to this prediction is that similar DNA sequences found in distant species must be functionally constrained.
This prediction has been falsified in the many examples of functionally-unconstrained, highly similar stretches of DNA that have been discovered in otherwise distant species. For instance, thousands of so-called ultra-conserved elements (UCEs), hundreds of base pairs in length, have been found across a range of species including human, mouse, rat, dog, chicken and fish. In fact, across the different species some of these sequences are 100% identical. Species that are supposed to have been evolving independently for 80 million years were certainly not expected to have identical DNA segments. “I about fell off my chair,” remarked one evolutionist. (Lurie) “It can’t be true” another commented. (Pennisi)
Evolutionists assumed such highly preserved sequences must have an important function. But laboratory studies failed to reveal any significant effects in mice. A variety of experiments were done to determine the function of these sequences that evolution was supposed to have preserved. But in many of the regions no function could be found. One study deleted several UCE regions, including a stretch of 731 DNA base pairs that was hypothesized to regulate a crucial gene. Evolutionists expected the removal to result in lethality or infertility but instead found normal, healthy mice. Months of observation and a battery of tests found no abnormalities or significant differences compared to normal mice. (Ahituv, et. al.) As one of the lead researchers explained:
For us, this was a really surprising result. We fully expected to demonstrate the vital role these ultraconserved elements play by showing what happens when they are missing. Instead, our knockout mice were not only viable and fertile but showed no critical abnormalities in growth, longevity, pathology, or metabolism. (Mice thrive missing ancient DNA sequences)
Another study knocked out two massive, highly conserved, DNA regions of 1.5 million and .8 million base pairs in laboratory mice and, again, the results were viable mice, indistinguishable from normal mice in every characteristic they measured, including growth, metabolic functions, longevity and overall development. (Nobrega, et. al.) “We were quite amazed,” explained the lead researcher. (Westphal)
References
Ahituv, N., Y. Zhu, A. Visel, A. Holt, V. Afzal, L. Pennacchio, E. Rubin. 2007. “Deletion of ultraconserved elements yields viable mice.” PLoS Biol 5:e234.
Lurie, Karen. 2004. “Junk DNA.” ScienCentral July 20.
“Mice thrive missing ancient DNA sequences.” 2007. ScienceDaily September 6. http://www.sciencedaily.com/releases/2007/09/070904151351.htm
Nobrega, M., Y. Zhu, I. Plajzer-Frick, V. Afzal, E. Rubin. 2004. “Megabase deletions of gene deserts result in viable mice.” Nature 431:988-993.
Pennisi, Elizabeth. 2004. “Disposable DNA puzzles researchers.” Science 304:1590-1591.
Westphal, S. 2004. “Life goes on without ‘vital’ DNA.” New Scientist June 3.
As different species evolve, their DNA segments are preserved only if they contribute to the organism’s fitness. DNA segments that are not functionally constrained should mutate and diverge over time. The result is that similar yet functionally unconstrained DNA segments should not be found in distant species. The corollary to this prediction is that similar DNA sequences found in distant species must be functionally constrained.
This prediction has been falsified in the many examples of functionally-unconstrained, highly similar stretches of DNA that have been discovered in otherwise distant species. For instance, thousands of so-called ultra-conserved elements (UCEs), hundreds of base pairs in length, have been found across a range of species including human, mouse, rat, dog, chicken and fish. In fact, across the different species some of these sequences are 100% identical. Species that are supposed to have been evolving independently for 80 million years were certainly not expected to have identical DNA segments. “I about fell off my chair,” remarked one evolutionist. (Lurie) “It can’t be true” another commented. (Pennisi)
Evolutionists assumed such highly preserved sequences must have an important function. But laboratory studies failed to reveal any significant effects in mice. A variety of experiments were done to determine the function of these sequences that evolution was supposed to have preserved. But in many of the regions no function could be found. One study deleted several UCE regions, including a stretch of 731 DNA base pairs that was hypothesized to regulate a crucial gene. Evolutionists expected the removal to result in lethality or infertility but instead found normal, healthy mice. Months of observation and a battery of tests found no abnormalities or significant differences compared to normal mice. (Ahituv, et. al.) As one of the lead researchers explained:
For us, this was a really surprising result. We fully expected to demonstrate the vital role these ultraconserved elements play by showing what happens when they are missing. Instead, our knockout mice were not only viable and fertile but showed no critical abnormalities in growth, longevity, pathology, or metabolism. (Mice thrive missing ancient DNA sequences)
Another study knocked out two massive, highly conserved, DNA regions of 1.5 million and .8 million base pairs in laboratory mice and, again, the results were viable mice, indistinguishable from normal mice in every characteristic they measured, including growth, metabolic functions, longevity and overall development. (Nobrega, et. al.) “We were quite amazed,” explained the lead researcher. (Westphal)
References
Ahituv, N., Y. Zhu, A. Visel, A. Holt, V. Afzal, L. Pennacchio, E. Rubin. 2007. “Deletion of ultraconserved elements yields viable mice.” PLoS Biol 5:e234.
Lurie, Karen. 2004. “Junk DNA.” ScienCentral July 20.
“Mice thrive missing ancient DNA sequences.” 2007. ScienceDaily September 6. http://www.sciencedaily.com/releases/2007/09/070904151351.htm
Nobrega, M., Y. Zhu, I. Plajzer-Frick, V. Afzal, E. Rubin. 2004. “Megabase deletions of gene deserts result in viable mice.” Nature 431:988-993.
Pennisi, Elizabeth. 2004. “Disposable DNA puzzles researchers.” Science 304:1590-1591.
Westphal, S. 2004. “Life goes on without ‘vital’ DNA.” New Scientist June 3.
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