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By calling to their eggs, zebra finch parents may be helping their young prepare for a hotter world brought on by climate change.

Almost every cell in your body has the same DNA sequence. So how come a heart cell is different from a brain cell? Cells use their DNA code in different ways, depending on their jobs. Just like orchestras can perform one piece of music in many different ways. A cell's combined set of changes in gene expression is called its epigenome. This week Nature publishes a slew of new data on the epigenomic landscape in lots of different cells. Learn how epigenomics works in this video. Read the latest research on epigenetics at http://www.nature.com/epigenomeroadmap

Researchers led by Terra D. Barnes of Washington University discovered that their genetically-engineered mice stutter due to DNA defects in a humdrum "housekeeping" gene. This gene codes for a protein that simply places a "routing tag" on certain enzymes that shred cellular trash. The tag ensures that the shredding enzymes end up in chambers called lysosomes, basically the cell's garbage disposal. It's a mundane cellular activity, yet mutations in the same process in humans have also been linked to stuttering-a bizarrely specific condition for such a general gene. And, so far, scientists have no idea why the two are linked.

In a study published Thursday in the journal Science, they report that they've pinpointed the bit of finch DNA behind the swift transition: a gene called HMGA2. In finches, HMGA2 seems to be the primary factor in beak size - like a really good group project leader, it orchestrates the expression of a number of other genes, each of which tweaks the size of the bird's beak. The same gene also appears in dogs, horses, even humans, holding sway over body size and stature.

Research has shown that some older people stay sharp into old age and retain the ability to recall personal experiences with just as much accuracy as their middle-aged peers. The brains of these so-called "super-agers" look distinct, too: Their gray-matter-rich outer layer, or cortex, is thicker.

23min video Cells are everywhere. They are the basic structural, functional and biological units of all known living organisms. Cells are the smallest unit of life that is classified as a living thing, and are often called the "building blocks of life". But, there's more...

Fact sheet: Metastatic cancer is cancer that has spread from the place where it first started to another place in the body. A tumor formed by metastatic cancer cells is called a metastatic tumor or a metastasis.

NIMR scientists have devised a genetic multi-colour cell labelling approach for Drosophila, called Flybow, to facilitate the visualization of cells in neural circuits with single cell resolution. The research is published in Nature Methods.

After apologizing for an American science experiment in which Guatemalan prisoners and mentally ill patients were deliberately infected with STDs more than 60 years ago, U.S. officials called on the Institute of Medicine to launch a full investigation. NBC Chief Science Correspondent Robert Bazell reports.

The Future of Research is being decided now! While we are fortunate to have a robust system of protections in place that help assure research will provide more benefit than harm, the regulations that guide research with human participants have been in place for 40 years. Society is changing, technology is changing, the capabilities and interests of all of us are changing. We need to evolve our research systems too. It is increasingly hard for one group to decide what would be considered a benefit, or a harm, for another. In this new People Matter Project video, we call to institutions and Institutional Review Boards (IRBs) to think creatively about how to conduct trustworthy research in this changing climate.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome.

In 1932, the Public Health Service, working with the Tuskegee Institute, began a study to record the natural history of syphilis in hopes of justifying treatment programs for blacks. It was called the "Tuskegee Study of Untreated Syphilis in the Negro Male."

Our genomes are riddled with the detritus of ancient viruses. They infected our hominid ancestors tens of millions of years ago, inserting their genes into the DNA of their hosts. Today, we carry about 100,000 genetic remnants of this invasion. So-called endogenous retroviruses make up 8 percent of the human genome.

Within a year, Stein's team had designed a clinical trial protocol that turned standard research practices around 180 degrees, launching what it now calls the Signature Clinical Trial Program. Instead of a patient traveling to one of several research sites, Novartis would send the investigational drugs to his or her local oncologist's office. Instead of testing hundreds or thousands of genetically unscreened patients, the company would accept only patients who had the genetic markers the drugs were supposed to target. Instead of waiting months, patients could access the treatments in two or three weeks. Instead of running a large-scale trial to investigate one or two questions, clinicians could conduct smaller, rapid proof-of-concept studies to quickly rule out the tumor types that don't respond to a study agent and identify other tumor types that are potentially treatable with the drug and worthy of further study.

Some people in the world aren't able to see many colors. The condition is called color blindness, but what exactly causes it?

Have you ever wondered why people look the way they do? Why our hands and feet have five digits instead of six? Why we stand on two legs instead of four? It took 350 million years of evolution to produce the amazing machine we call the human body and in Your Inner Fish, a three-part series based on the best-selling book of the same name, author and evolutionary biologist Dr. Neil Shubin looks into the past to answer these and other questions.

2:18 Human embryonic development depends on stem cells. During the course of development, cells divide, migrate, and specialize. Early in development, a group of cells called the inner cell mass (ICM) forms. These cells are able to produce all the tissues of the body. Later in development, during gastrulation, the three germ layers form, and most cells become more restricted in the types of cells that they can produce.

The most recent human retroviral infections leading to germ line integration took place with a subgroup of human endogenous retroviruses called HERVK(HML-2). The human genome contains ~90 copies of these viral genomes, which might have infected human ancestors as recently as 200,000 years ago. HERVs do not produce infectious virus: not only is the viral genome silenced - no mRNAs are produced - but they are littered with lethal mutations that have accumulated over time. A recent study revealed that HERVK mRNAs are produced during normal human embryogenesis. Viral RNAs were detected beginning at the 8-cell stage, through epiblast cells in preimplantation embryos, until formation of embryonic stem cells (illustrated). At this point the production of HERVK mRNA ceases. Viral capsid protein was detected in blastocysts, and electron microscopy revealed the presence of virus-like particles similar to those found in reconstructed HERVK particles. These results indicate that retroviral proteins and particles are present during human development, up until implantation.

How are the stages of mitosis related to the creation of identical daughter cells? The primary function of the stages of mitosis is to make certain that each daughter cell is genetically identical to the mother cell. The mother cell's DNA is copied during interphase. During mitosis the chromosomes condense from long strands to highly coiled structures. The two copies of each DNA strand, called sister chromatids, are physically attached to one another. The chromosomes are moved to the center of the cell and split apart in a highly coordinated fashion. The condensation of the chromosomes, the physical connection of the sister chromatids, and the precise movement of the chromosomes are all important in making sure that each daughter cell has one copy of each chromosome and is genetically identical to the mother cell.

The cellular life cycle, also called the cell cycle, includes many processes necessary for successful self-replication. Beyond carrying out the tasks of routine metabolism, the cell must duplicate its components - most importantly, its genome - so that it can physically split into two complete daughter cells. The cell must also pass through a series of checkpoints that ensure conditions are favorable for division.