Genetics & Molecular Biology

Most science talks I listen to, even good ones, leave me dissatisfied because the stories I hear never come to a complete resolution. The issue is this: we can get from traits to genes, and from genes to molecular biology. But we have largely failed at getting from molecular biology back to the characteristics of organisms. We don't do a good job explaining organismal traits with molecular biology.
UCL (University College London) scientists studying face recognition in identical twins say the essential skill is largely determined by our genetics. Published today in the Proceedings of the National Academy of Sciences, the study found that identical twins were twice as similar to each other in terms of their ability to recognize faces, compared to non-identical twins.

Researchers also found that the genetic effects that allow people to recognize faces are linked to a highly specific mechanism in the brain, unrelated to other brain processes such as the ability to recognize words or abstract art.
A new RNA molecule created by University of Colorado scientists can catalyze a key reaction needed to synthesize proteins. The discovery may have significant implications, researchers say, because it further substantiates the 'RNA World' hypothesis, which proposes that life on Earth evolved from early forms of RNA. The research is detailed this week in the Proceedings of the National Academy of Sciences.
There is a new article out in today’s Molecular System Biology, which has the media saying the typical baloney-filled things like “The Key to Aging Discovered,” “Breakthrough to Immortality,” and “Live Forever?”

The enzyme calcineurin is critical to normal development and function of heart cells, and loss of the protein leads to heart problems and death in genetically modified mice, according to researchers at Cincinnati Children's Hospital Medical Center

Their new study, published in the Journal of Biological Chemistry, demonstrates that calcineurin in hearts of mice is directly linked to proper cardiac muscle contraction, rhythm and maintenance of heart activity. The near total absence of calcineurin in mice leads to heart arrhythmia, failure and death, according to the research team.
Writing in Cell, a team of biologists say they have unraveled the biochemistry of how bacteria so precisely time cell division, a key element in understanding how all organisms from bacteria to humans use their biological clocks to control basic cellular functions. The discovery provides important clues to how the biological clocks of bacteria and other "prokaryotic" cells—which lack cell nuclei—evolved differently from that of "eukaryotic" cells with nuclei that comprise most other forms of life, from fungi to plants and animals.
A recent study in the American Journal of Human Genetics has revealed how human genes interact with their environment to boost disease risk. The authors say the findings shed light on why the search for specific gene variants linked to human diseases can only partly explain common disorders.
Scientists have known that newly acquired, short-term memories are often fleeting, but a new study of Drosophila in Cell suggests that there is a good reason for that kind of forgetfulness. An active process of erasing memories may be as important as the ability to lay down new memories.

"Learning activates the biochemical formation of memory," says Yi Zhong of Tsinghua University and Cold Spring Harbor Laboratory. "But you need to remove memories for new information to come in. We've found that forgetting is an active process to remove memory."
Biologists have struggled for many years to explain how it is possible that some people who carry a mutated gene don't express the trait or condition associated with the mutation. This common but poorly understood phenomenon, known as incomplete penetrance,  may be partially due to environmental factors and the influence of other genes, but scientists say other forces are likely at work here as well.

The authors of a new study in Nature say that some cases of incomplete penetrance may be controlled by random fluctuations in gene expression.

In a study of intestinal development of C. elegans, a small worm, the team was able to pinpoint specific fluctuations that appear to determine whether the mutant trait is expressed or not.
DNA analysis of royal mummies suggest that malaria and bone abnormalities may have contributed to the death of Egyptian pharaoh King Tutankhamun, with other results appearing to identify members of the royal family, including King Tut’s father and mother, according to a new study published in the Journal of The American Medical Association. The findings may lead to a new way of researching the molecular genealogy and pathogen paleogenomics of the Pharaonic era, perhaps even a new field called 'molecular Egyptology.'