Reappearance of Missing Genetic Information Poses Exception to the Rule

March 23, 2005
Reappearance of Missing Genetic Information Poses Exception to the Rule

Code is hiding but not lost

Researchers have discovered that "missing" genetic information unexpectedly reappears in later generations. By poring over the genome of the model plant, Arabidopsis thaliana, scientists at Purdue University found specific genetic information present in a "grandparent" and "grandchild," even though it was seemingly absent in the "parent."
The study is featured in the March 24 issue of the journal Nature.

Image: Arabidopsis thaliana researchers have discovered that "missing" genetic information unexpectedly reappears in later generations yielding offspring with traits identical to the grandparent and not the parent. Credit: Zina Deretsky, National Science Foundation

For more than a century, a basic tenet of inheritance has dictated that an organism’s genome passes directly from one generation to the next in a predictable manner—from grandparents—to parents—to children. Now, Susan Lolle, Robert Pruitt and their colleagues have shown this cardinal rule of inheritance is sometimes broken. The scientists reached their conclusion by tracking how genetic information passes through multiple Arabidopsis generations. In violation of current genetic theory, they found a significant percentage of the plant grandchildren had genetic information identical to that of the grandparent, but not the parent.

But how could the child acquire genetic information from its grandparent, if the parent had lost it? Lolle and Pruitt postulate that the “lost” genetic information securely resides outside the standard genome and is only retrieved under particular circumstances when it may be beneficial to restore genomic sequences back to an ancestral state. So, the information was not lost, but rather “hidden”—from scientists anyway.

How does the plant benefit by accessing a cache of its ancestor’s genomic information? Lolle said, “This ancestral information acts like a reserve genetic template that plants can make use of should living conditions become less ideal.” She continued, “In this way, we think plants get a ‘second chance’ to win the genetic lottery.”

Like any good scientist, Lolle was skeptical of her own results and hesitant to believe something so novel was occurring. For years she reasoned there were trivial explanations for what she was seeing. Eventually, however, Lolle could no longer discount the evidence, so she meticulously repeated experiments and verified results, ruling out all explanations afforded by conventional dogma. The data became irrefutable—the genetic information was “skipping” a generation.

It’s a nearly heretical theory. Indeed, the implications will have scientists pondering old results anew. As Rita Teutonico, the National Science Foundation program manager who oversees this work said, “We knew the project was ambitious, but these results challenge us to re-think some genetic paradigms and demonstrate that some very forward thinking ideas warrant investigation.” Teutonico continued, “This result illustrates the benefits of the NSF’s support of bold, high-payoff science.”

Source: NSF

Explore further: Defying the laws of Mendelian inheritance

Related Stories

Defying the laws of Mendelian inheritance

February 4, 2013

Two articles published in F1000Research support controversial claims that could redefine what we know about Mendelian inheritance in single Arabidopsis thaliana plants.

New Clues in the Plant Mating Mystery

February 16, 2006

New data suggest that molecular communication between the plant sexes--specifically the pollen of males and pistils of females--is more complicated than originally thought. Plants, like animals, avoid inbreeding to maximize ...

Recommended for you

Researchers build bacteria's photosynthetic engine

July 29, 2015

Nearly all life on Earth depends on photosynthesis, the conversion of light energy into chemical energy. Oxygen-producing plants and cyanobacteria perfected this process 2.7 billion years ago. But the first photosynthetic ...

Dense star clusters shown to be binary black hole factories

July 29, 2015

The coalescence of two black holes—a very violent and exotic event—is one of the most sought-after observations of modern astronomy. But, as these mergers emit no light of any kind, finding such elusive events has been ...

Scientists unlock secrets of stars through aluminium

July 29, 2015

Physicists at the University of York have revealed a new understanding of nucleosynthesis in stars, providing insight into the role massive stars play in the evolution of the Milky Way and the origins of the Solar System.

Yarn from slaughterhouse waste

July 29, 2015

ETH researchers have developed a yarn from ordinary gelatine that has good qualities similar to those of merino wool fibers. Now they are working on making the yarn even more water resistant.

Studies reveal details of error correction in cell division

July 29, 2015

Cell biologists led by Thomas Maresca at the University of Massachusetts Amherst, with collaborators elsewhere, report an advance in understanding the workings of an error correction mechanism that helps cells detect and ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.