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Your genome, every human's genome, consists of a unique DNA sequence of A's, T's, C's and G's that tell your cells how to operate. Thanks to technological advances, scientists are now able to know the sequence of letters that makes up an individual genome relatively quickly and inexpensively. Mark J. Kiel takes an in-depth look at the science behind the sequence.

Your genome, every human's genome, consists of a unique DNA sequence of A's, T's, C's and G's that tell your cells how to operate. Thanks to technological advances, scientists are now able to know the sequence of letters that makes up an individual genome relatively quickly and inexpensively. Mark J. Kiel takes an in-depth look at the science behind the sequence.

Paul Strode describes the HHMI BioInteractive Click and Learn activity on DNA sequencing and phylogenetic trees. He describes how it teaches students DNA sequence alignment, and how those sequence differences allow researchers to determine relationships between species. Visit www.biointeractive.org/phylo-tree to use the interactive resource, and to find related materials. Subscribe to the BioInteractive YouTube channel to get the latest educator tips!

The 1000 Genomes Project is an international collaboration to produce an extensive public catalog of human genetic variation, including SNPs and structural variants, and their haplotype contexts. This resource will support genome-wide association studies and other medical research studies. The genomes of about 2500 unidentified people from about 25 populations around the world will be sequenced using next-generation sequencing technologies. The results of the study will be freely and publicly accessible to researchers worldwide. Further information about the project is available in the About tab. Information about downloading, browsing or using the 1000 Genomes data is available in the Data tab.

Autism is rooted in genetics, including the mutation of certain genes that result in a failure of neurons in the brain to properly connect. Based on earlier genetic research funded by Autism Speaks, such as the Autism Genome Project (AGP), scientists have discovered some of these genes. But much more gene discovery needs to take place. The Autism Genome 10K Project will mark a substantial leap forward on this journey. The Autism Genome 10K Project builds on the successes of Autism Speaks' Autism Genetic Resource Exchange program (AGRE), a high-quality collection of more than 12,000 DNA samples from families affected by autism. The AGRE program has facilitated many high-impact scientific discoveries in recent years, including the risk genes discovered by the AGP and other researchers. With BGI sequencing the full complement of 10,000 samples collected by AGRE and collaborators in China, Autism Genome 10K leverages BGI's cutting-edge expertise and globally unrivaled capacity for high-quality genome sequencing.

This Click and Learn explains how DNA sequences can be used to generate such trees, and how to interpret them.

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.

This interrupted case study examines molecular genetic evidence reported in scientific literature to determine the fate of Louis-Charles, son of Louis XVI and Marie-Antoinette of France. Controversy and rumors surrounding the death of Louis-Charles suggested that either he died as a young boy while being held in captivity by the French revolutionaries or he escaped and was replaced by a substitute who died in his place. One individual claiming to be Louis-Charles was Karl Naundorff. Students begin the case by preparing pedigrees for the descendants of Maria Theresa and Francis I, the Holy Roman Emperor, parents of Marie-Antoinette. The pedigrees can be used to introduce the concepts of alleles identical-by-descent and cytoplasmic inheritance patterns. Students then compare mitochondrial DNA sequences and XY chromosome sequences from hair, bone, heart, and blood samples taken from descendants of Marie Theresa, Karl Naundorff and the heart of the boy who died in captivity to determine if the latter was truly Louis-Charles. An optional PowerPoint presentation with clicker questions is available to help guide the classroom activities.

In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

Cool interface for analyzing sequence data; much mores student friendly than NCBI

As the leader of a project called Finding of Rare Disease Genes (FORGE) in Canada, Kym Boycott is one of the top experts in the world in the application of exome sequencing to solve rare disorders. The Canadian project involves a network of doctors and scientists all across the country looking to identify patients with rare childhood conditions and refer them when appropriate for sequencing and analysis.

In this lesson, students explore some of the risks and benefits of gene-based medicine. They look at concerns related to genetic testing (which looks for particular genetic variations) and personal genome sequencing (which sequences the entire genome of an individual). Through videos and discussions, students learn about existing technologies for genetic testing and therapies. They also explore matters such as the emotional consequences of genetic testing, discrimination, and privacy issues. In small groups, students discuss scenarios and then share and analyze related opinions and concerns.

4:43 video

By early 2014, Flint, Kendler and a team of collaborators had analysed DNA sequences from 5,303 Chinese women with depression, and another 5,337 controls. As Flint expected, 85% of the depressed women had a severe form of the disorder called melancholia, which robs people of the ability to feel joy. "You can be a doting grandparent and your favourite grandchildren can show up at your door," says Douglas Levinson, a psychiatrist at Stanford University in California, "and you can't feel anything." The analysis yielded two genetic sequences that seemed to be linked to depression: one in a stretch of DNA that codes for an enzyme whose function is not fully understood, and the other next to the gene SIRT1, which is important for energy-producing cell structures called mitochondria. The correlations were confirmed in another set of more than 3,000 depressed men and women and over 3,000 controls.

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 two-minute video provides brief background on the use of zebrafish as a model in studying animal development, before showing a time-lapse sequence of a fertilized zebrafish egg developing into a larva.  The video includes some annotations that help orient the viewer during the time-lapse sequence.  Teachers might want to mute the narration beginning at 0:42 min to avoid giving students too much information.  This phenomenon could stimulate the following driving questions: How does the zebrafish develop from one cell to the many cells that make up the larva? How do the zebrafish cells divide? How are the developing zebrafish cells similar and different from each other? If all cells in the zebrafish develop from the same original cell, then how do some cells develop differently than others? How are cell division and growth related? 

"Scientists have sequenced the complete genome of the naked mole rat, a pivotal step to understanding the animal's extraordinarily long life and good health."

3:27 video introduces genetics and DNA sequence

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

This video excerpt from NOVA uncovers the genetic mystery that nearly killed Alexis, now 14, and introduces the debate surrounding genetic testing at birth. After diagnosing Alexis and her twin brother Noah with cerebral palsy at a young age, doctors later discovered that the twins shared a rare genetic mutation that led to a condition that mimics cerebral palsy. The twins improved after receiving treatment, but then Alexis took a turn for the worse. Thanks to whole genome sequencing, doctors discovered a second problem linked to the mutation and gave her a different treatment that saved her life.