This site contains user-friendly tools to launch DNA database searches, statistical analyses, and population modeling from a centralized workspace. Educational databases support investigations of an Alu insertion polymorphism on human chromosome 16 and single nucleotide polymorphisms (SNPs) in the human mitochondrial control region.

In this guide, the information has been broken down into six sections: DNA Timeline, Code, Manipulation, Genome, Applications, Chronicle. Each section includes teacher pages, alignment with the national science education standards, student worksheets, answer sheets and templates.

Genetic engineering is responsible for the so-called "second green revolution."  Genes that encode herbicide resistance, insect resistance, drought tolerance, frost tolerance, and other traits have been added to many plants of commercial importance. In 2003, 167 million acres of farmland worldwide were planted in genetically modified (GM) crops equal to one fourth of total land under cultivation.  The most widely planted GM crops are soybeans, corn, cotton, canola, and papaya. Two important transgenes have been widely introduced into crop plants.  The Bt gene, from Bacillus thuringiensis, produces a toxin that protects against caterpillars, reducing applications of insecticides and increasing yields. The glyphosate resistance gene protects food plants against the broad-spectrum herbicide Roundup, which efficiently kills invasive weeds in the field. The major advantages of the "Roundup Ready®" system include better weed control, reduction of crop injury, higher yield, and lower environmental impact than traditional herbicide systems. Most Americans would probably be surprised to learn that more than 60% of fresh vegetables and processed foods sold in supermarkets today are genetically modified by gene transfer.  In 2004, approximately 85% of soy and 45% of corn grown in the U.S. were grown from Roundup Ready® seed.

Throughout the first half of the 20th century, geneticists assumed that a stable genome was a prerequisite for faithfully transmitting genes from one generation to the next.  Working at Cold Spring Harbor Laboratory in the post-WWII era, Barbara McClintock found quite a different story in maize (corn).  She observed numerous “dissociations” – broken and ring-shaped chromosomes – and traced the source of these mutations to the short arm of chromosome 9.  There she identified two related loci,   “dissociator” (Ds) and “activator” (Ac).

Dynamic Gene is designed to let students learn about plant genomes by using bioinformatics to analyze newly sequenced genes in rice and maize. Many of these genes have only been predicted by computers and have never been closely examined by human beings! The site's name emphasizes the gene both as a dynamic structure that changes through evolutionary time, but also as a dynamic concept that changes with our increasing knowledge of genome organization. The design for Dynamic Gene recalls the "streamlining movement" that influenced design during the middle of the 20th century with ideas borrowed from aviation and automobile design.

The goal of the Genetic Origins Program is to allow students to use their own DNA variations (polymorphisms) as a means to explore our shared genetic heritage and its implications for human health and society. Genetic Origins focuses on two types of DNA variations: an Alu insertion polymorphism on chromosome 16 (PV92) and single nucleotide polymorphisms (SNPs) in the control region of the mitochondrial (mt) chromosome. With two alleles and three genotypes, PV92 is a simple genetic system that illustrates Mendelian inheritance on a molecular level. PV92 data is readily analyzed using population statistics. The mt control region is one of the simplest regions of human DNA to sequence. With a high mutation rate, the mt control region is the "classical" system for studying human and primate evolution. The Genetic Origins site and linked Bioservers site have all the information needed for students to perform the Alu and mt DNA experiments and analyze the results - including online protocols, reagents, animations and videos explaining key concepts, and database tools.

The Greenomes site is part of a laboratory- and Internet-based curriculum to bring college students up to the minute with modern plant research. Plant molecular genetic and genomic research still lags behind medically-oriented research on microbes and higher animals. As a result, there are relatively few lab experiences that expose college-level students to the growing insights into plants offered by genomic biology.

Hallmarks of cancer, causes and preventions, diagnoses and treatment are explained.

Since Alfred Sturtevant constructed the first genetic map of a Drosophilachromosome in 1913, new mutations have been mapped using his method of linkage analysis. Determining the map position of a new mutation -- and its corresponding gene -- consists of testing for linkage with a number of previously mapped genes or DNA markers. Linkage is the principle that the closer two genes or markers are located to one another on a chromosome, the greater the chance that they will be inherited together as a unit (linked).  Conversely, locations farther apart on the chromosome are more likely to be separated by chromosome recombination during meiosis. Thus, the frequency of recombination with previously mapped genes or markers allows one to determine the map position of a gene of interest. The increasing availability of whole genome sequences and sophisticated computer software has made it possible to map genes using bioinformatic approaches.  However, traditional mapping techniques are still used to map genes for which no sequence information is available -- for example, mutant phenotypes produced by chemical mutagenesis.  Although early gene maps relied on genes and mutations with observable phenotypes, modern gene maps are populated with DNA polymorphisms that are detected by molecular methods. In Arabidopsis, molecular markers exploit the natural differences between distinct ecotypes, such as the widely used Landsberg (Ler) and Columbia (Col), which differ about 1% at the DNA level.