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The article "The difference makers" (10.9 readability score) gives an overview of transposons, or "jumping genes," and how these bits of genetic material have affected genetic variety and evolution in humans and other organisms. Students can focus on details reported in the article, follow connections to earlier articles about transposons and human evolution, explore crosscurricular connections to other major science topics, and construct a phylogenetic tree of primate evolution based on the locations of retroviral sequence insertions in chromosome 21

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.)

Book Chapter of gene therapy, nice figure on different approaches.

Most siblings with a diagnosis of autism do not share the same genetic risk factors for the disorder and are as distinct in their behaviors as any brothers and sisters, scientists reported on Monday in a study that came as a surprise to many doctors, if not to parents.

Using a pre-drawn template can be helpful during a consultation to explain single gene inheritance. Our template shows one pair of chromosomes for each parent. Each chromosome has a single gene highlighted that can be coloured in to illustrate a gene alteration. You can then show which sperm and/or eggs contain the chromosome with the gene alteration and the different genetic combinations that could be present at conception.

Since this time, research has focused on biological factors that may lead to autistic behaviours. This has found very clearly there is no one cause of autism. A variety of genetic factors are likely to be the ultimate cause of most cases of autism. These may work by themselves, or in combination with environmental factors, to lead a child's brain to develop differently and result in autistic behaviours.

A gene mutation is a permanent alteration in the DNA sequence that makes up a gene, such that the sequence differs from what is found in most people. Mutations range in size; they can affect anywhere from a single DNA building block (base pair) to a large segment of a chromosome that includes multiple genes.

This case study presents the mock trial of "Martin Miller." There is no question that Martin killed his girlfriend; he admitted to stabbing her in a violent rage. But what is the degree of his responsibility? By virtue of Martin having the MAOA-L gene variant, together with a history of childhood abuse, should his punishment be reduced? This hypothetical case, which requires students to think through the issues rather than simply look up a verdict, is based on actual events and violent behaviors that resulted in criminal charges claimed to be related to MAOA. The MAOA gene and its effect on behavior have been extensively studied, and research results have been introduced as evidence in court cases with differing results. The present case study allows students to explore how behavioral genetic information can be applied to a courtroom situation, and requires them to integrate information from biology, ethics, and the law. Note: Due to the unusual structure of the case, no answer key is available.

Sometimes, a genetic tweak can make a really big difference in an animal's appearance. That's what likely happened when the predecessors of modern snakes lost their legs, a process that started some 150 million years ago, two separate groups of scientists have discovered. Although the teams took very different approaches to solve the mystery of how those limbs vanished, both came up with similar results: Mutations in DNA located near a gene key to limb formation keep that gene from ever turning on, they report today.

When you look at yourself in the mirror you may ask, 'How, given that all the cells in my body carry the same DNA, can my organs look so unlike and function so differently?' With the recent progress in epigenetics, we are beginning to understand. We now know that cells use their genetic material in different ways: genes are switched on and off, resulting in the astonishing level of differentiation within our bodies.

This case study centers on symbiotic relationships between insects and bacteria using Drosophila melanogaster, the common fruit fly, and the recently discovered bacterial species Sodalis praecaptivus. Until recently, the only known Sodalis species of bacteria were symbiotically associated with several different species of insects. However, free-living non-symbiont Sodalis species are being tested in several different insect species to determine if they can transition into symbiotic relationships. A pre-class assignment (see Supplemental Materials) directs students to read an open access research journal article providing a comprehensive review of S. praecaptivus and describing an experimental weevil model that parallels that of the fruit fly. A PowerPoint presentation shown in class (see Supplemental Materials) provides further background before students work in small groups to complete the case study focusing on results from D. melanogaster and S. praecaptivus model experiments.  Although developed for a genetics course, this interrupted case is appropriate for an upper-level biology course. It can be completed within a 75-minute class meeting, or adapted for shorter time periods.

Why did you get the flu this winter, but your co-workers didn't? The answer, according to a new study of twins, may have less to do with your genes and more to do with your environment-including your past exposure to pathogens and vaccines. Our immune system is incredibly complex, with diverse armies of white blood cells and signal-sending proteins coursing through our veins, ready to mount an attack on would-be invaders. Everyone's immune system is slightly different-a unique mixture of hundreds of these cells and proteins. But the main driver of this variation is unclear. Although scientists know that our immune system can adapt to our environment-that's why vaccines work, for instance-it is also built by our genes.

Learn how to set up and solve a genetic problem involving multiple alleles using ABO blood types as an example! The Amoeba Sisters walk you through the different phenotypes/genotypes of ABO blood types and how to solve these problems using a Punnett square.

Biologists estimate that there are about 5 to 100 million species of organisms living on Earth today. Evidence from morphological, biochemical, and gene sequence data suggests that all organisms on Earth are genetically related, and the genealogical relationships of living things can be represented by a vast evolutionary tree, the Tree of Life. The Tree of Life then represents the phylogeny of organisms, i. e., the history of organismal lineages as they change through time. It implies that different species arise from previous forms via descent, and that all organisms, from the smallest microbe to the largest plants and vertebrates, are connected by the passage of genes along the branches of the phylogenetic tree that links all of Life (Figure 1).

Inthis lesson students will enter the world of the genome, learning about humanhistory and evolution by examining information about human, Neanderthal, andchimpanzee DNA. Using web interactives and videosfrom The Human Spark, studentswill be introduced to the ambitious Human Genome Project, learn about thegenetic similarities and differences between human beings and our hominidancestors, explore how specific genes manifest themselves in differentorganisms, and discover how genetic information can help us trace a path ofhuman migration all the way back to our earliest ancestors.

The origin of viruses remains mysterious because of their diverse and patchy molecular and functional makeup. Although numerous hypotheses have attempted to explain viral origins, none is backed by substantive data. We take full advantage of the wealth of available protein structural and functional data to explore the evolution of the proteomic makeup of thousands of cells and viruses. Despite the extremely reduced nature of viral proteomes, we established an ancient origin of the "viral supergroup" and the existence of widespread episodes of horizontal transfer of genetic information. Viruses harboring different replicon types and infecting distantly related hosts shared many metabolic and informational protein structural domains of ancient origin that were also widespread in cellular proteomes. Phylogenomic analysis uncovered a universal tree of life and revealed that modern viruses reduced from multiple ancient cells that harbored segmented RNA genomes and coexisted with the ancestors of modern cells. The model for the origin and evolution of viruses and cells is backed by strong genomic and structural evidence and can be reconciled with existing models of viral evolution if one considers viruses to have originated from ancient cells and not from modern counterparts.

A complete understanding of evolution requires knowledge that spans many biological sub-disciplines. However, students are often taught evolution in the context of ecological systems and isolated from genetic and cellular ones. To address this issue, we have developed case studies that track the evolution of traits from their origination in DNA mutation, to the production of different proteins, to the fixation of alternate macroscopic phenotypes in reproductively isolated populations.

A decade-old technique that allows researchers to control brain function in lab animals could partially restore sight to the blind. In a trial sponsored by RetroSense Therapeutics, a startup company in Ann Arbor, Michigan, doctors will inject a harmless virus loaded with DNA from photoreceptive algae into the eyes of 15 patients suffering from retinitis pigmentosa. The experimental procedure represents the first human test of optogenetics, which is a technique that genetically modifies neurons to make them responsive to light. Doctors from the Retina Foundation of the Southwest will perform the procedure, and attempt to transfer the job duties of photoreceptor cells to different cells in the eye to restore sight.

As the prevalence of genetically modified organisms (GMOs) continues to rise, there has been an increasing public interest for information concerning the safety of these products. Concerns generally focus on how the GMO may affect the environment or how it may affect the consumer. One specific concern is the possibility for GMOs to negatively affect human health. This could result from differences in nutritional content, allergic response, or undesired side effects such as toxicity, organ damage, or gene transfer.

Gene flow is the transfer of genetic material between separate populations. Many organisms are divided into separate populations that have restricted contact with each other, possibly leading to reproductive isolation. Many things can fragment a species into a collection of isolated populations. For example, a treacherous mountain pass may cut off one herd of mountain goats from another. In human beings, cultural differences as well as geographic separation maintain unique populations: It is more likely that a person will marry and have children with someone who lives nearby and speaks the same language.