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This interactive case discussion was created to emphasize the clinical relevance of population genetics, but is also a suitable resource for teaching the basic principles of population genetics while relating them to human genetic variation. Our understanding of human genetic variation has deepened over the past decade due to fine-scale genome mapping. Applying this knowledge to the evaluation of ancestry-based genetic testing strategies, such as direct-to-consumer genetic testing, is an important component of the practice of culturally-competent medicine and a relevant way to teach the foundations of population genetics, including Hardy-Weinberg equilibrium.

Genetic studies of human disease are more challenging to perform in sub-Saharan Africa because genetic diversity is greater than in other populations. This pilot will increase our understanding of African genome variation and enable the design of large-scale genetic association studies in the region. Studies into the genetic basis of disease in European populations have made major advances in the past few years, yet similar studies in sub-Saharan Africa have been slower to develop. The high level of genetic diversity that exists in populations from sub-Saharan Africa makes genetic associations with disease more difficult to identify. The African Genome Variation Project aims to collect essential information about the structure of African genomes to provide a basic framework for genetic disease studies in Africa.

Bipolar disorder is a common, complex genetic disorder, but the mode of transmission remains to be discovered. Many researchers assume that common genomic variants carry some risk for manifesting the disease. The research community has celebrated the first genome-wide significant associations between common single nucleotide polymorphisms (SNPs) and bipolar disorder. Currently, attempts are under way to translate these findings into clinical practice, genetic counseling, and predictive testing. However, some experts remain cautious. After all, common variants explain only a very small percentage of the genetic risk, and functional consequences of the discovered SNPs are inconclusive. Furthermore, the associated SNPs are not disease specific, and the majority of individuals with a "risk" allele are healthy. On the other hand, population-based genome-wide studies in psychiatric disorders have rediscovered rare structural variants and mutations in genes, which were previously known to cause genetic syndromes and monogenic Mendelian disorders.

This hands-on activity, used in conjunction with the film The Making of the Fittest: Natural Selection in Humans, teaches students about population genetics, the Hardy-Weinberg principle, and how natural selection alters the frequency distribution of heritable traits. It uses simple simulations to illustrate these complex concepts and includes exercises such as calculating allele and genotype frequencies, graphing and interpretation of data, and designing experiments to reinforce key concepts in population genetics.

7:00 video: This film is the first of a two part series on the evolution of new genetic information. Here we focus on Point Mutations - the simplest natural mechanisms known to increase the genetic information of a population. Our second film of the series will focus on duplication events - natural mutations that increase the total amount of genetic information of an individual. This film was produced under the guidance of molecular biologist Dr. Nicholas Casewell. http://www.lstmed.ac.uk/about/people/... Point mutations are small, natural edits in the DNA code of an individual. These edits can be passed from parent to child. Because they are mere edits, point mutations usually do not increase the total amount of information in an individual. As new information is gained, old information is lost. Point mutations do, however, increase the total amount of information within a population. In this film you will see several examples of beneficial point mutations which have enhanced a creatures abilities or even given rise to entirely new abilities. The first two examples were directly observed in bacteria by scientists in the lab. The third is a case found in domestic dogs, the last example was discovered in several species of wild animal.

In population genetics, gene flow (also known as gene migration) is the transfer of alleles or genes from one population to another. Migration into or out of a population may be responsible for a marked change in allele frequencies (the proportion of members carrying a particular variant of a gene). Immigration may also result in the addition of new genetic variants to the established gene pool of a particular species or population.

This lesson, using segments from the PBS series Faces of America, explores the various types of genetic information contained in the human genome. The Introductory Activity examines the structure and composition of chromosomes and DNA, and can be used as a review or introduction to the topic. Following that, students will participate in a hands-on activity reviewing basic Mendelian genetics and the difference between genotype and phenotype. Students will also learn about different ways of tracing ancestry through DNA, and apply that to patterns of human migration and genetic population sets known as haplogroups. In the Culminating Activity, students will develop methods for determining the genetic heritage of their class, school, or community.

The Hardy-Weinberg equation is a relatively simple mathematical equation that describes a very important principle of population genetics: the amount of genetic variation in a population will remain the same from generation to generation unless there are factors driving the frequencies of certain alleles (genetic variants) to change.

"This modular case study tells the story of Dan and Annie, a married couple of Acadian ancestry who have a genetic form of deafblindness called Usher syndrome. They live in Southwest Louisiana, home of the largest population of DeafBlind citizens in the United States. Acadian Usher syndrome is caused by an allele of the USH1C gene that came to Louisiana with the first Acadian settlers from Canada who founded today's Cajun population. This allele's single nucleotide substitution creates an erroneous splice site that produces a defective cytoskeletal protein (harmonin) of the cochlear and vestibular hair cells and retinal photoreceptors. This splice site is the target of a promising gene therapy. The case study applies and connects Mendelian inheritance, chromosomes, cell division, vision and hearing, DNA sequences, gene expression, gene therapy and population genetics to a specific gene and its movement through generations of Dan and Annie's families.  After the introduction, each of the remaining sections can be used independently either for in-class team activities or out-of-class extensions or assignments over an entire year of introductory undergraduate biology. "

Dogs are excellent models for studying genetics, especially disease genetics. Work done in the last 20 years has shown that dogs share many gene-related disorders with people. Each breed is a closed reproductive population with distinct rates of heritable diseases, which dramatically increases the odds of finding disease-related loci. In creating new dog breeds, we reduce the gene pool within those populations, and fix many alleles. This homogeneous background makes it much easier to map QTLs and perform linkage analyses

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.

Sub-Saharan Africa is the most genetically diverse region in the world." The rates of susceptibility and not only whether or not someone becomes ill, but also whether or not they live or die, or even display symptoms, varies widely. The genetics of both this deadly strain of Ebola itself, and of the populations living in the affected areas, are at the forefront of the efforts by Dr. Moses as she works with Dr.Pardis Sabeti at Harvard to provide samples for genome sequencing.

Over the past few decades, genetic research has revealed two deep truths about people. The first is that all humans are closely related-more closely related than all chimps, even though there are many more humans around today. Everyone has the same collection of genes, but with the exception of identical twins, everyone has slightly different versions of some of them. Studies of this genetic diversity have allowed scientists to reconstruct a kind of family tree of human populations. That has revealed the second deep truth: In a very real sense, all people alive today are Africans.

This lesson examines issues stemming from genetic databanks and population genetics studies

Although Hardy-Weinberg equilibrium is a fundamental part of introductory biology classes, students often have difficulty understanding its implications. This interrupted case study places students in the role of small teams who are conducting preliminary research into the impact of roads on the population structure of timber rattlesnakes in order to apply for a grant for further research. Research groups consisting of 3-4 students work through a series of questions allowing them to use HWE principles to discover for themselves how deviations from HWE can have implications for conservation biology. Periodic interruptions with help sheets (see Supplemental Materials) allow teachers to maintain an active role in the students' progress, while also demonstrating the collaborative nature of scientific research. Ultimately students formulate formal emails summarizing and interpreting their findings in order to "apply" for the grant. The case is designed for undergraduate students in introductory biology or in lower-level population genetics/conservation courses where connecting basic genetic principles to ecology and sustainability is key.

Text and interactives on human evolution and genetic structure

Five distinct humpback whale populations have been identified across the North Pacific Ocean in the most comprehensive genetic study of the mammals in this region yet, a new study reports.

Genetic differences among ethnically diverse individuals are largely due to structural elements called copy number variants (CNVs), according to a study published today (August 6) in Science. Compared with other genomic features, such as single nucleotide variants (SNVs), CNVs have not previously been studied in as much detail because they are more difficult to sequence. Covering 125 distinct human populations around the world, geneticist Evan Eichler at the University of Washington in Seattle and an international team of colleagues studied the genomes of 236 people-analyzing both SNVs and CNVs. "The take-home message is that we continue to find a lot more genetic variation between humans than we appreciated previously," Eichler told The Scientist.

All living humans originated from populations of ancestors who migrated out of Africa less than 100,000 years ago. Learn how scientists have used genetic markers to trace the migration routes and origins of modern human populations.

his resource describes an inquiry-based, in-class exercise designed for students working in small groups. It is designed to review and enrich student understanding of probability, how probabilities of individual events can be combined to make predictions about more complex outcomes, and how observed data can be compared to a null model based on probabilities using a chi-squared test. These skills are used extensively for classical genetic analysis. Throughout the activity, peers and instructors guide students through the process of developing and solving problems using probabilities and chi-squared tests in small groups.