[__ Science __ ] New Genetic Information Proposals Fail

[AIG.com]

Getting new genetic information is required for evolution—but every proposed (and imaginative) method for obtaining it fizzles one way or another

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[Barbarian]

Getting new genetic information is required for evolution—but every proposed (and imaginative) method for obtaining it fizzles one way or another

This is a common misconception, but it's false. Indeed, evolutionary change often happens by a loss of genetic information. Founder effect, which is a common way new species evolve, is the loss of information in a small, isolated population of a species, due to fewer individuals and less genetic variation. Then, as time goes on, mutations will produce additional information. An example is the rapid speciation of flies in Hawaii from just one or two species that happened to get that far. A huge percentage of the total genetic information of Drosophila is found in Hawaii alone.

New information was assumed to be mostly by gene duplication, followed by mutation, (which has been observed), but scientists have now found that many times, it happens by genes forming from non-coding DNA (sometimes called by creationists, "junk DNA") It's usual function is to control gene expression, but sometimes, a mutation will produce a new gene from formerly non-gene DNA:

"Where do new genes come from?" is a long-standing question in genetics and evolutionary biology. A new study from researchers at the University of California, Davis, published Jan. 23 in Science Express, shows that new genes are created from non-coding DNA more rapidly than expected.

"This shows very clearly that genes are being born from ancestral sequences all the time," said David Begun, professor of evolution and ecology at UC Davis and senior author on the paper.

Geneticists have long puzzled about how completely new genes appear. In a well-known model proposed by geneticist Susumu Ohno, new functions appear when existing genes are duplicated and then diverge in function. Begun's laboratory discovered a few years ago that new genes could also appear from previously non-coding stretches of DNA, and similar effects have since been discovered in other animals and plants.

"This is the first example of totally new genes still spreading through a species," said Li Zhao, a postdoctoral researcher at UC Davis and first author on the paper.

Zhao looked at RNA transcripts -- corresponding to expressed genes -- in the testes of several wild-derived strains of the fruit fly Drosophila melanogaster, and compared them to transcripts expressed in the standard reference sequence strain and in two closely related species. She found 248 new genes that exist only in D. melanogaster, just over a hundred of which were "fixed," or already spread throughout the population.

These genes emerged from ancestrally non-coding DNA since D. melanogaster split from its close relative, D. simulans.

New genes spring from non-coding DNA

"Where do new genes come from?" is a long-standing question in genetics and evolutionary biology. A new study from researchers at the University of California, Davis, published Jan. 23 in Science Express, shows that new genes are created from non-coding DNA more rapidly than expected. "This...

www.ucdavis.edu

The other source of new genetic information:
Gene Duplications are a common starting point for the evolution of new genetic information. When gene duplications occur, they dramatically lengthen the genetic code of an individual. As point mutations add up in the duplicated region across generations, entirely new genes with new functions can evolve.

Scientists have directly and indirectly observed gene duplication events in the lab and in wild populations of plants, animals and microbes, many times over. Because of this, they can use known signatures of gene duplication events to understand how a large variety of genes evolved in plants and animals alive today.

How Does New Genetic Information Evolve? Part 2: Gene Duplications • Stated Clearly

Here we see how new genetic information evolves via gene duplications followed by point mutations.

www.statedclearly.com

 

[Truthfrees]

Getting new genetic information is required for evolution—but every proposed (and imaginative) method for obtaining it fizzles one way or another

Continue reading...

not surprised

 

[Barbarian]

As usual, AIG is behind the curve a few decades. While new information does arise by gene duplication, followed by mutation (something which is often observed), it is now known that many new genes arise by mutation of non-coding DNA (what creationists often call "junk DNA").

Geneticists have long puzzled about how completely new genes appear. In a well-known model proposed by geneticist Susumu Ohno, new functions appear when existing genes are duplicated and then diverge in function. Begun's laboratory discovered a few years ago that new genes could also appear from previously non-coding stretches of DNA, and similar effects have since been discovered in other animals and plants.

"This is the first example of totally new genes still spreading through a species," said Li Zhao, a postdoctoral researcher at UC Davis and first author on the paper.

Zhao looked at RNA transcripts -- corresponding to expressed genes -- in the testes of several wild-derived strains of the fruit fly Drosophila melanogaster, and compared them to transcripts expressed in the standard reference sequence strain and in two closely related species. She found 248 new genes that exist only in D. melanogaster, just over a hundred of which were "fixed," or already spread throughout the population.

New genes spring from non-coding DNA

"Where do new genes come from?" is a long-standing question in genetics and evolutionary biology. A new study from researchers at the University of California, Davis, published Jan. 23 in Science Express, shows that new genes are created from non-coding DNA more rapidly than expected. "This...

www.ucdavis.edu

As we demonstrated some time ago, any new allele or new gene in a population increases information. If anyone would like to see the numbers again, I'd be pleased to show this.