World Community Grid - Research - Nutritious Rice for the World

The objective of this project is to predict the structure of proteins of major strains of rice. The intent is to help farmers breed better rice strains with higher crop yields, promote greater disease and pest resistance, and utilize a full range of bioavailable nutrients that can benefit people around the world, especially in regions where hunger is a critical concern.

Determining the structure of proteins is an extremely difficult and expensive process. However, it is possible to computationally predict a protein's structure from its corresponding DNA sequence. The Computational Biology Research Group at the University of Washington has developed state of the art software to accomplish this. The difficulty is, there are thousands of distinct proteins found in rice. This presents a computational challenge that a single computer cannot solve within a reasonable timeframe. Therefore, volunteers of World Community Grid are invited to assist in this daunting task. Through collaboration with agricultural researchers and farmers, the hope is to eventually improve global rice yields and quality.

World Community Grid - Research - Nutritious Rice for the World

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Culture Speeds Up Human Evolution

Homo sapiens sapiens has spread across the globe and increased vastly in numbers over the past 50,000 years or so—from an estimated five million in 9000 B.C. to roughly 6.5 billion today. More people means more opportunity for mutations to creep into the basic human genome and new research confirms that in the past 10,000 years a host of changes to everything from digestion to bones has been taking place.

"We found very many human genes undergoing selection," says anthropologist Gregory Cochran of the University of Utah, a member of the team that analyzed the 3.9 million genes showing the most variation. "Most are very recent, so much so that the rate of human evolution over the past few thousand years is far greater than it has been over the past few million years."

"We believe that this can be explained by an increase in the strength of selection as people became agriculturalists—a major ecological change—and a vast increase in the number of favorable mutations as agriculture led to increased population size," he adds.

Roughly 10,000 years ago, humanity made the transition from living off the land to actively raising crops and domesticated animals. Because this concentrated populations, diseases such as malaria, smallpox and tuberculosis, among others, became more virulent. At the same time, the new agriculturally based diet offered its own challenges—including iron deficiency from lack of meat, cavities and, ultimately, shorter stature due to poor nutrition, says anthropologist John Hawks of the University of Wisconsin–Madison, another team member.

"Their bodies and teeth shrank. Their brains shrank, too," he adds. "But they started to get new alleles [alternative gene forms] that helped them digest the food more efficiently. New protective alleles allowed a fraction of people to survive the dread illnesses better."

Three Smart Things You Should Know About Genomics

1. The real benefit of studying genomes is that it has taught us how little we know. We used to think noncoding "junk" DNA didn't do anything. Now it turns out it may contain underlying instructions for how DNA works.

2. Genomics' reductionist approach has become more holistic. Now we also look at all the proteins a cell makes (proteomics), RNA transcription (transcriptomics), molecules that control which DNA gets turned on (epigenomics), and cell energy consumption (metabolomics).

3. Important genes usually exist in multiple copies, in case one iteration gets damaged. This results in lots of leftover, deactivated genes from up the evolutionary tree — solid molecular proof that Darwin was right — birds have genes for teeth; humans share genes with gorillas.

Samoan butterfly population shows evolution at work: study

The dramatic comeback of a tropical male butterfly, which was almost wiped out of existence by an invasive parasite, shows just how fast natural selection can work in practice, researchers said Thursday.

When researchers sampled the numbers of the Blue Moon butterfly species on the South Pacific island of Savaii at the beginning of 2006, the males accounted for just one percent of the population.

By the end of the year, a period that is equivalent to 10 generations of Blue Moon butterflies, that figure had jumped to almost 40 percent.

Investigators believe the comeback is due to the proliferation of "suppressor" genes that hold in check the Wolbachia bacteria that is passed down from the mother and kills male embryos before they can hatch.

"To my knowledge, this is the fastest evolutionary change that has ever been observed," said Sylvain Charlat, lead author on the study and a post-doctoral researcher at the University of California, Berkeley.

"This study shows that when a population experiences very intense selective pressures, such as an extremely skewed sex ratio, evolution can happen very fast."

"We usually think of natural selection as acting slowly, over hundreds of thousands of years," added Gregory Hurst, a senior author on the paper and a researcher in evolutionary genetics at University College London.

"But the example in this study happened in the blink of the eye, in terms of evolutionary time, and is a remarkable thing to get to observe."

Charlat and his colleagues first documented the massive imbalance in the sex ratio of the butterfly species on Savaii and the neighbouring island of Upolu in 2001. At that point, the male butterfly was extremely rare, making up just one percent of the total population.

In 2006, the team embarked on a new survey after an increase in reports of male sightings at Upolu.

They found that the sex ratio among the latest crop of insects, (scientific name Hypolimnas bolina) was 1:1 on Upolu and approaching parity on Savaii, even though the female insects were still infected with the Wolbachia parasite, and it was still capable of killing the male of the species.

It is not yet clear whether the suppressor gene emerged from a chance mutation from within the local population, or if it was introduced by migratory Southeast Asian butterflies in which the mutation had already been established.

"But regardless of which of the two sources of the suppressor gene is correct, natural selection is the next step. The suppressor gene allows infected females to produce males, these males will mate with many, many females and the suppressor gene will therefore be in more and more individuals over generations," Charlat explained.

Overall, the waxing and waning fortunes of the male Blue Moon butterfly shows that not only how fast species can evolve, or adapt, but just how important parasites can be as evolutionary drivers, the authors said.

"In the case of H. bolina, we're witnessing an evolutionary arms race between the parasite and the host. This strengthens the view that parasites can be major drivers in evolution," said Charlat.

First Decoded Marsupial Genome Reveals "Junk DNA" Surprise

Marsupials are the closest living relatives of placental mammals. The two groups split from a common ancestor about 180 million years ago.

Scientists were able to pinpoint the genetic elements that are present in placental mammals but missing from marsupials to learn more about what makes the two groups different.

The researchers were surprised to find that placental and marsupial mammals have largely the same set of genes for making proteins. Instead, much of the difference lies in the controls that turn genes on and off.