2007年6月14日星期四

Heredity

What is genetics and genomics? Genetics is a term that refers to the study of genes and their role in inheritance - the way certain traits or conditions are passed down from one generation to another. Genetics involves scientific studies of single genes and their effects. Genes (units of heredity) carry the instructions for making proteins, which direct the activities of cells and functions of the body. Genes influence traits such as hair and eye color as well as health and disease development. Genetics determines much (but not all) of a person's appearance and health status, but environmental differences also play a part. Examples of single gene disorders that would be considered as ”genetics” include cystic fibrosis and PKU (phenylketonuria). Genomics is a relatively new term that describes the study of all of a person's genes including interactions of those genes with each other and the person's environment. Genomics involves the scientific study of complex diseases such as heart disease, asthma, diabetes and cancer because they are caused more by a combination of genetic and environmental factors. Genomics is offering new possibilities for therapies and treatment of some diseases, as well as new diagnostic methods. The major tools and methods related to genomics studies are bioinformatics, genetic analysis, measurement of gene expression, and determination of gene function. Why is genetics and genomics important to my health? Genetics and genomics both play a role in health and disease. Genetics helps individuals and families learn about how conditions, such as sickle cell anemia, are inherited in families; what screening and testing is available; and in for some genetic conditions, treatment. (See: Frequently Asked Questions About Genetic Disorders) Genomics is helping to discover why some people get sick from certain infections, environmental factors, and behaviors, while others do not. For example, there are some people who exercise their whole lives, eat a healthy diet, have regular medical checkups, and who die of a heart attack at age 40. There are also people who smoke, never exercise, eat unhealthy foods, and live to be 100. Genomics holds the key to these differences. Genomics has a role in 9 of the 10 leading causes of death in the United States (for example, heart disease, cancer, diabetes). All human beings are 99.9 percent identical in their genetic makeup. Differences in the remaining 0.1% hold important clues about the causes of diseases. Having a better understanding of the interactions between genes and the environment is helping us find better ways to improve health and prevent disease. Why is genetics and genomics important to my family's health? Understanding more about single gene disorders (genetics) and complex diseases (genomics) can lead to earlier diagnosis, interventions and targeted treatments. A person's health is influenced by his/her family history and shared environmental factors. Family history is an important, personalized tool that captures many of the gene/environment interactions, for conditions that are genetic and genomic in origin. The family history can serve as the cornerstone for learning about genetic and genomic conditions in a family and for individualized disease prevention. (See: My Family Health Portrait). What are some of the new genetic and genomic technologies? Proteomics The suffix ”ome” comes from the Greek for 'all', 'every' or 'complete.' It was originally used in ”genome,” which refers to the complete genetic makeup of a person or organism. Due to the success of the large-scale biology projects such as genome sequencing, the suffix ”ome” is now being used in other research contexts. Proteomics is an example. The term proteome refers to the total number of proteins (expressed genes that are translated into proteins) in an organism, tissue type or cell. Proteomics is now a well-established term for studying the proteome. Pharmacogenetics and Pharmacogenomics Pharmacogenetics is the field of study dealing with the variability of responses to medications due to genetic variation. Pharmacogenetics takes into account a person's genetic information regarding how drugs are transported and metabolized by the body, and their specific drug receptors. The goal of pharmacogenetics is to create an individualized drug therapy that allows for the best choice and dose of drugs. Pharmacogenomics is the research area that involves the search for genetic variations that are associated with drug efficiency. The term comes from the words pharmacology and genomics, and is the intersection between pharmaceuticals and genomics. Pharmacogenomics is leading to drugs that can be tailor-made for individuals, and adapted to each person's own genetic makeup. Although a person's environment, diet, age, lifestyle, and state of health can influence that person's response to medicines, understanding an individual's genetic makeup is key to creating personalized drugs that are work better and with fewer side-effects. (See: Genetics, Disease Prevention and Treatment) Stem Cell Therapy Stem cells are unspecialized cells - human or animal - that can make specialized body cells and at the same time make copies (replicate) themselves. Embryonic stem cells come from the embryo at a very early stage in development (called the blastocyst). The stem cells in the blastocyst go on to develop into a person or animal. Adult stem cells come from the umbilical cord or from the blood, bone marrow, skin and other tissues. Medical researchers are investigating the use of stem cells to repair or replace damaged body tissues. This is because stem cells are less likely than other, foreign, cells to be rejected by a patient's immune system when they are placed in the body. Embryonic stem cells have the ability to develop into every type of tissue (skin, liver, kidney, etc) found in an adult human. Adult stem cells do not have the same ability. Stem cells have been used in experiments to form cells of the bone marrow, heart, blood vessels and muscle. Beginning in the 1990's umbilical cord blood stem cells have been used to treat heart and other physical problems in children who have rare metabolic conditions or to treat children with certain anemias and leukemias. There has been much debate nationally about the use of embryonic stem cells, especially creating human embryos for use in experiments. Congress enacted a ban in 1995 on federal financing for research in human embryos. However, these restrictions have not stopped researchers in the United States and elsewhere from using private funding to create new embryonic cell lines and undertaking research with them. Cloning A clone is a genetically identical cell population that comes from a common ancestor. To clone an organism means to make a genetically identical copy of that organism. Cloning DNA (genes) involves manipulation to make multiple copies of a single gene or groups of genetically identical cells from the same ancestor gene. Human cloning involves the creation of a genetically identical copy of an existing, or previously existing human, or growing cloned tissue from an individual. The stem cells used in cloning usually are taken from extra, fertilized embryos created during in vitro fertilization procedures. Some medical researchers have used embryos that were fertilized specifically to make stem cells. This is called ”therapeutic cloning.” Therapeutic cloning involves taking the nucleus (within a body cell) from a body cell such as, a liver cell, and inserting it into an egg that has had its nucleus removed to produce an embryonic stem cell (blastocyst) whose stem cells could then be used to create tissue that is the same as the patient's. The first clones were frogs. Dolly, the famous sheep is another example of cloning. The success rates of animal cloning, however, have been very low. Human cloning was reported in 2005 to have been successful by South Korean researchers. These researchers claimed to produce stem cell lines using genetic material from patients. However, this data was later reported as falsified. GeneGene, Elsevier Science. Volume: 376. Issue: 1, July 5, 2006, pp. 1-161. Volume: 375. Complete, June 21, 2006, pp. 1-113. Volume: 374. Complete, June 7, 2006, pp. 1-181. Volume: 373. Complete, May 24, 2006, pp. 1-146. Volume: 372 ... elsevier.lib.tsinghua.edu.cn/cgi-bin/sciserv.pl?collection=journals&journal=03781119 - Gene - ElsevierLetters to the Editor are selected for publication that are pertinent to material published in GENE or that discuss problems of general interest. The author of a paper in question is usually given an opportunity to reply. ... www.elsevier.com/locate/gene - Gene - Wikipedia, the free encyclopediaThis stylistic schematic diagram shows a gene in relation to the double helix structure of DNA and to a chromosome (right). Introns are regions often found in eukaryote genes which are removed in the splicing process: only the exons ... en.wikipedia.org/wiki/Gene - Genentech - A Biotechnology Research CompanyGenentech Inc., the founder of the biotechnology industry, is a pioneer in biotechnology research and is a leading biotechnology company. It discovers, develops, manufactures and markets biopharmaceuticals for significant unmet medical ... www.gene.com/ - Hangzhou Jiuyuan Gene Engineering Co.,LtdHangzhou Jiuyuan Gene Engineering Co., Ltd is located in the state-grade Hangzhou Economic & Technological Development Zone, P.R.China. Jiuyuan is a modern joint venture specializing in the research, development, production and ... www.china-gene.com/ - Gene Macintosh Genealogy SoftwareShareware genealogy software for Macintosh to store family data, print family trees and pedigree charts, and create web pages from database. www.ics.uci.edu/~eppstein/gene/ - Gene Finderand protein coding exons, construct gene model and recognize the promotor and poly-A region. Place the DNA sequence < 7000 bp in the query box. ... predict gene structure and identify exons using additional information becomes available ... www.bioscience.org/urllists/genefind.htm - Gene Expression PatternsGene Expression Patterns, Elsevier Science. Volume: 6. Issue: 6, August, 2006, pp. 581-665. Issue: 5, June, 2006, pp. 443-577. Issue: 4, April, 2006, pp. 333-439. Issue: 3, March, 2006, pp. 235-331. Issue: 2, January, 2006, pp. 125-234 ... elsevier.lib.tsinghua.edu.cn/cgi-bin/sciserv.pl?collection=journals&journal=1567133X - Gene TherapyRecent scientific breakthroughs in the genomics field and our understanding of the important role of genes in disease has made gene therapy one of the most rapidly advancing fields of biotechnology with great promise for treating ... cmbi.bjmu.edu.cn/cmbidata/therapy/index/index.htm - Hypertension Candidate Gene SNPSWe have made all hypertension candidate gene SNPs detected through the collaboration of Affymetrix Inc. and the Chakravarti laboratory at Case Western Reserve University available here. Below is a list of 116 candidate genes for which ... cmbi.bjmu.edu.cn/genome/candidates/snps.html - eServer Blue Gene Solution TOP500 Supercomputing SitesSite, IBM Thomas J. Watson Research Center. System Family, IBM BlueGene/L. System Model, eServer Blue Gene Solution. Computer, eServer Blue Gene Solution. Vendor, IBM/ LLNL. Application area, Not Specified. Installation Year, 2005 ... www.top500.org/system/7634 - eServer Blue Gene Solution TOP500 Supercomputing SitesSystem Family, IBM BlueGene/L. System Model, eServer Blue Gene Solution. Computer, eServer Blue Gene Solution. Vendor, IBM. Application area, Research. Installation Year, 2005. Performance/Linpack Data ... www.top500.org/system/7689 - Bacterial Polysaccharide Gene DatabaseFrom here you can specify a search of the Bacterial Polysaccharide Gene Database. The results of the search will be returned as a ”hit list”. From the hit list you follow links to look at individual records from the database in greater ... www.mmb.usyd.edu.au/BPGD/default.htm -