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This two-hour special, hosted by ABC "Nightline" correspondent Robert Krulwich, chronicles the fiercely competitive race to capture one of the biggest scientific prizes ever: the complete letter-by-letter sequence of genetic information that defines human life-the human genome. NOVA tells the story of the genome triumph and its profound implications for medicine and human health.

3:27 video introduces genetics and DNA sequence

The agricultural revolution was one of the most profound events in human history, leading to the rise of modern civilization. Now, in the first study of its kind, an international team of scientists has found that after agriculture arrived in Europe 8,500 years ago, people's DNA underwent widespread changes, altering their height, digestion, immune system and skin color. Researchers had found indirect clues of some of these alterations by studying the genomes of living Europeans. But the new study, they said, makes it possible to see the changes as they occurred over thousands of years.

11:02 TED talk on genomic sequencing and impending changes in health care.

The fates of ice age human groups in Europe were closely linked to climate change, according to an unprecedented study of the genomes of 51 individuals who lived between 45,000 years ago (when modern humans arrived in Europe) and 7,000 years ago. "We see multiple, huge movements of people displacing previous ones," David Reich of the Harvard Medical School said. "During this first four-fifths of modern human history in Europe, history is just as complicated as it is during the last fifth that we know so much more about." 

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Researchers analysed the genomes of 51 individuals who lived between 45,000 years ago and 7,000 years ago. The results reveal details about the biology of these early inhabitants, such as skin and eye colour, and how different populations were related. It also shows that Neanderthal ancestry in Europeans has been shrinking over time, perhaps due to natural selection. The study in Nature journal shines a torchlight over some 40,000 years of prehistory, showing that ancient patterns of migration were just as complex as those in more recent times.

3:16 video

3:30 video

Redwood trees, those ancient living monuments to California's past, are as mysterious to science as they are magnificent, so a team of researchers led by a San Francisco conservation group is attempting to unlock the genetic secrets of the towering conifers. Scientists affiliated with the nonprofit Save the Redwoods League are attempting for the first time to sequence the genomes of coast redwood trees and their higher-elevation cousins, the giant sequoias, a complex and expensive undertaking that experts hope will help preserve the trees' ancient groves as the climate changes over the next century.

This 8-minute video is derived from the 2013 Holiday Lectures on Science. In it, Dr. Charles Sawyers explains the difference between proto-oncogenes, oncogenes, and tumor suppressor genes, and how mutations in these genes drive cancer development. "Cancer genes" can affect several cellular processes that he groups into three categories: cell growth and survival (i.e., genes involved in the cell cycle, cell fate (i.e., genes involved in cell differentiation), and genome maintenance (i.e, genes involved in DNA repair.)

The advent of increasingly powerful and inexpensive DNA sequencing methods is changing many aspects of genetics research. In particular, human genome sequencing is transforming our understanding of many aspects of human biology and medicine. However, we must be careful to remember that genes alone do not determine our futures-environmental factors and chance also play important roles.

A stride to understand the cancer and move towards its prevention, this time experts from around the world involved in searching the genome of cancer have analyzed the mutational signatures, the processes of mutation in the DNA of cells (which are always in the origin of cancer) and they follow a fixed pattern.

Three years ago, Dr. Doudna, a biochemist at the University of California, Berkeley, helped make one of the most monumental discoveries in biology: a relatively easy way to alter any organism's DNA, just as a computer user can edit a word in a document.

The early stages of embryonic development shape our cells and tissues for life. It is during this time that our newly formed cells are transformed into heart, skin, nerve or other cell types. Scientists are finding that this process is largely controlled not by the genome, but by the epigenome, chemical markers on DNA that tell cells when to turn genes on and off. Now, studying zebrafish embryos, researchers at Washington University School of Medicine in St. Louis have shown that the epigenome plays a significant part in guiding development in the first 24 hours after fertilization.

Questions about the nature of viruses remain quite vexing. Recent studies of the giant Mimivirus illustrate this point. Its large size and correspondingly large genome test our general ideas of viruses as small, simple entities. The existence of genes associated with translation, metabolism, DNA repair, and protein folding raises questions about the evolutionary history of viruses. Further studies of this virus, and the search for other giant viruses, may shed light on these issues.

The mouse is the leading organism for disease research. A rich resource of genetic variation occurs naturally in inbred and special strains owing to spontaneous mutations. However, one can also obtain desired gene mutations by using the following processes: targeted mutations that eliminate function in the whole organism or in a specific tissue; forward genetic screens using chemicals or transposons; or the introduction of exogenous transgenes as DNAs, bacterial artificial chromosomes (BACs) or reporter constructs. The mouse is the only mammal that provides such a rich resource of genetic diversity coupled with the potential for extensive genome manipulation, and is therefore a powerful application for modeling human disease.

A British researcher has received permission to use a powerful new genome editing technique on human embryos, even though researchers throughout the world are observing a voluntary moratorium on making changes to DNA that could be passed down to subsequent generations.

As the genomes of more and more species are sequenced, geneticists are piecing together an extraordinarily detailed picture of the molecules that are fundamental to life on Earth. With modern techniques, we can not only trace how the bodies of animals have evolved, we can even identify the genetic mutations behind these changes and, as we recently reported, genes sometimes evolve in surprising ways. Here though, in celebration of the versatility of DNA, New Scientist presents five classic examples of gene evolution.

Séguin, a research scientist in forest genomics with the Canadian Forest Service, inserted bacterial DNA into spruces that effectively made them immune to spruce budworm, a pest that can chew needles off tens of millions of hectares of trees in a single outbreak. While there is controversy over genetic engineering, some scientists say it could also help fight climate change by creating trees that grow bigger, faster, resist disease and can even turn carbon into a stable white powder that falls to the ground - in other words, trees that would be better at pulling carbon from the atmosphere.