necessarily represent the views of the funding agency.”
Genetics and Public Health in the 21st Century
COMMUNICATION, EDUCATION, AND INFORMATION DISSEMINATION
Using the Internet to Disseminate Genetics Information for Public Health
Leslie A. O'Leary1 and Debra L. Collins2
1Office of Genomics and Disease Prevention, Centers for Disease Control and Prevention, 4770 Buford Hwy, MS K28, Atlanta, GA 30341
2University of Kansas Medical Center, Kansas City, KS 66160-7318
As a result of the Human Genome Project, most, if not all, of our 60,000 - 80,000 genes will be mapped and sequenced by the year 2003 (1). Already, genes are being discovered at an incredible pace. Although most of the genes that have been identified are associated with rare genetic disorders, genes that confer susceptibility to common diseases such as cancer, heart disease, and diabetes are also being discovered. As these "susceptibility" genes are identified, clinical and epidemiologic data regarding their association with specific diseases will become available. This information will have tremendous impact on public health, particularly in terms of disease prevention and health promotion. Therefore, it is crucial that the information be distributed both accurately and rapidly.
The traditional method of disseminating scientific information to the medical and public health community has been primarily through publication of peer-reviewed manuscripts in journals. Unfortunately, this process often delays the release of important information for several months to years. As data from the Human Genome Project accumulate rapidly, a new approach for disseminating this information is crucial. The Internet is an approach by which information can be distributed inexpensively to millions of people both rapidly and accurately. This chapter will focus on the use of the Internet as a method of disseminating genetic information for public health.
Although many people think of the Internet as a recent development, its origin dates back to the 1960s when the Advanced Research Projects Agency (ARPA), a research and development agency of the United States Department of Defense, developed a computer communication network that became known as ARPANET. ARPANET revolutionized the communication world and provided the foundation for the Internet (2).
The objective of ARPANET was to link computers located at various scientific laboratories across the country so that computer resources could be shared among researchers. In 1969, the first four computers, located at the University of California at Los Angeles, the Stanford Research Institute, the University of California at Santa Barbara, and the University of Utah, were linked (2). Before long, computers from other areas (e.g., Harvard University, Carnegie Mellon University) were added, and ARPANET began to grow.
The first public demonstration of ARPANET was held in October, 1972, at the 1st International Conference on Computer Communication in Washington, D.C. (2). Soon after, other countries began developing their own networks, but ARPANET remained the largest and most sophisticated. However, during the 1980s, other networks such as CSNET, BITNET, and NSFNET were being developed, and by the end of 1989, ARPANET had been dissolved; sites were removed from ARPANET and put on NSFNET (2). NSFNET was faster and easier to connect to than ARPANET and became the backbone for what is now called the Internet.
During the 1980s, the Internet was used primarily by academic, governmental, and private research organizations. However, Internet usage exploded in the early 1990s when individual access to the Internet became available via commercial providers. In 1981, there were approximately 230 computers on the Internet; as of January 1998, more than 29 million computers were on the Internet, and the number continues to grow (3). Currently, the Internet is not only being used by academic, governmental, and private research organizations, but it is also being used commercially to advertise and sell products. Because of its capability to distribute information rapidly, accurately, and inexpensively, the Internet has become one of the most popular methods of disseminating information.
The most fascinating features of the Internet are the services and information it provides. The most commonly used services include electronic mail (e-mail), the file transfer protocol (FTP), and the World Wide Web (WWW). Electronic mail, defined as messages sent and received electronically, is the most frequently used feature of the Internet and is the primary reason for its heavy use. Originating in the 1960s, email has become one of the most effective means of communication. It is fast, reliable, and inexpensive and allows people to communicate with each other regardless of geographic boundaries. An e-mail address consists of two parts, the username and the hostname, which are separated by the symbol "@". A type of electronic mail that has become increasingly popular is mail distributed through mailing lists. Mailing lists allow people to send a message to an e-mail address where the message is copied and then sent to all members who subscribe to the mailing list, thus enabling a person to communicate simultaneously with multiple people worldwide. Most mailing lists focus on a specific subject. For example, the genetics mailing list (email@example.com), which is moderated by the Office of Genomics and Disease Prevention at the Centers for Disease Control and Prevention, focuses on information related to genetics and public health.
Another commonly used Internet service is the file transfer protocol (FTP). The FTP makes possible the transfer of files between computers on the Internet. Using FTP and the Internet, people can distribute software or documents rapidly and inexpensively. For example, public health researchers from around the world can transfer information to each other within a matter of a few seconds, as well as access documents such as the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report (4).
When most people talk about the Internet, they are usually referring to the World Wide Web (WWW). The WWW, which is a multimedia branch of the Internet, was developed in 1990 by researchers at the European Laboratory for Particle Physics (CERN) as a method of sharing information among physicists (2,5). The WWW is a network of documents linked together by hypertext that can be accessed by clicking on highlighted text with a mouse. The documents can contain information in the form of text, graphics, video clips, or sound. Currently, the WWW is the predominant mechanism by which people access the Internet.
Search Engines and Finding Information on the Internet
New World Wide Web resources are added or updated frequently in response to new technology, including improvements in hardware and Internet browsers. With the plethora of World Wide Web information available, search engines are invaluable. Many (e.g., AltaVista, HotBot, Northern Light, Lycos, Infoseek) use keyword searches; however, each search engine produces different search results because of the differences in indexing systems used. Metasearch sites use several search engines simultaneously and rank the results.
Search engines use software, referred to as spiders, robots, or worms, to index a database of downloaded documents and resources (with titles, URLs, headers, full text, and other information) from various hosts linked to the Internet. A few thousand to more than a million Web sites or pages may be included, depending on the search engine's database and the quality of the indexing.
All search engines provide a link to the sites retrieved in the results displayed, usually in order of relevance. The ranking of the information sought will depend on the keywords used, the way the search was requested, and the way the information on the page is indexed by a search engine. Some sites are also available in multiple languages and are accessible for the visually impaired through speech-translation programs.
Each search tool provides instructions for its use. The Frequently Asked Questions (FAQ) section is updated regularly and describes new features. There is no single comprehensive search tool for the Web, and more than one search engine may be needed to find information. Some tips for using search engines are provided below:
- Use the most unique or unusual word associated with the topic.
- Use quotation marks around phrases; otherwise, the terms are searched individually.
- Note spelling errors and variations (e.g., color/colour)
- Use Boolean operators (AND, OR, NOT, or other operators) to keep a search from yielding too much, or too little, information.
- Use advance search features such as adjacency, proximity, or truncation.
- Use specific field searches (such as URL or title), date, media type, and/or location.
- Note that some search engines allow "plain-English" word order, phrase, case-sensitive, and field-based searching.
- Note that some search engines specifically search the Web, ftp sites, newsgroup articles, telnet sites, e-mail addresses, and/or electronic-news headlines.
- Note that some search engines allow searches in languages other than English.
- Note that new locations of established sites are often announced prominently in clinical journals. One can also find relocated sites with searching tools by using keywords specific for the resource. Medical center librarians may be helpful as well.
Progress in the Human Genome Project has lead to an explosion of genetic information. Genes are being discovered on a weekly basis, with more than 10,000 genes identified thus far (6). In addition, genetic tests are being developed and marketed to the general public at an incredible pace. Currently, more than 700 genetics tests are available for medical practice (7). Due to the plethora of genetic information that is forthcoming, Sikorski and Peters (8) predict that most of the up-to-date information necessary to practice genomic medicine will be found on the Internet. Because of the potential impact this information may have on society in terms of disease prevention and health promotion, it is essential that public health professionals are educated in the field of medical genetics.
The Internet is changing the way people learn. Traditionally people were educated via lectures and books in a classroom setting. Nowadays, much of the material that was previously presented in classroom format can now be found on the Internet. As an example, the Global Health Network (9) has developed an Internet-based course in epidemiology and the Internet to educate medical students and those in other health-related professions from around the world. The objectives of the course, referred to as the Supercourse - Epidemiology, the Internet and Global Health (10), are to provide an overview of 1) epidemiology using case examples, 2) the Internet using the interactive medium and 3) the integration of epidemiology/public health and the Internet. It is likely that similar courses related to genetics and public health will also soon be available on the Internet.
Several Web sites that contain educational information on genetics are now accessible on the Internet. The information contained on these Web sites varies in both level and content, ranging from material suitable for the general public to information geared toward health professionals and researchers. The Information for Genetic Professionals Web site (11) at the University of Kansas Medical Center provides links to clinical, research, and educational resources for genetic counselors, clinical geneticists, and medical geneticists. Information on training programs in genetics is also available on the Internet. The University of Pittsburgh's Graduate School of Public Health, which offers a degree program in human genetics (12), and the University of Michigan, which offers an interdepartmental program in public health genetics (13) have Web sites that provide information on their training programs. Information on other training programs in genetics or public health is available on the Internet and can be obtained by using search engines or by visiting a university's Web site.
The goals of public health are to reduce disease, premature death, and disability in populations. These goals are accomplished in a variety of ways through a multidisciplinary approach consisting of science, programs, and services. However, a critical component to improving the health of the public is information exchange and communication. Because the Internet has no geographic boundaries, it is an excellent mechanism for disseminating public health information. Already many of the medical and scientific journals (e.g., British Medical Journal (14), American Society of Human Genetics (15) , American Journal of Public Health (16)) can be accessed online (most with a paid subscription).
As the Internet gained popularity in the 1990s, its potential as a mechanism of disseminating information to improve public health worldwide became recognized (17). Today, use of the Internet in public health is increasing. Most state health departments (e.g., New York State Department of Health (18)), as well as federal (e.g., Centers for Disease Control and Prevention, (19)) and international health organizations (e.g., World Health Organizations, (20)) have developed sites on the WWW. Most of these sites have contact information to assist people who have questions or need further information.
With the plethora of genetics information that is forthcoming as a result of the Human Genome Project, it is not surprising that many public health professionals are turning to the Internet for genetic information. Information on gene variants, laboratories that do genetic testing, policy statements, and patient support organizations is available on the WWW. For example, if a public health researcher needs information on gene variants associated with cystic fibrosis they can access this information from an online genetic database such as the Online Mendelian Inheritance In Man (OMIM™) (21). Similarly, if information is requested on laboratories that do genetic testing for cystic fibrosis one could access the GeneTests™ (7) Web site, which is an online directory of laboratories that provide testing for genetic disorders. Although these resources may not currently be available for all diseases, it is likely that as the information becomes available for other disorders it will be put on the Internet.
Public health organizations are not only turning to the Internet to obtain information, but many are also designing Web sites that are specific to their own genetics program. For example, many state health departments, as well as federal and international agencies, have developed Web sites that are specific to their genetics programs (e.g., California Department of Health Services Genetic Disease Branch, (22)). The Office of Genomics and Disease Prevention at the Centers for Disease Control and Prevention maintains a Web site that provides access to current information about the impact of human genetic research on public health and disease prevention (23). Included on this Web site are links to other sites (e.g., genetic databases, regional and state genetics programs) that contain pertinent information on genetics and public health.
A Web site that is currently being developed that will be useful to public health officials, as well as researches and policy makers is the Human Genome Epidemiology Network (HuGE Net) Web site (24). This Web site contains the cumulative (and often changing) information on epidemiologic aspects of human genes, ranging from the prevalence of gene variants in various populations to the evaluation of genetic test and services. Other features of the site will include 1) updated medical literature searches for specific genes; 2) links to Internet sites and databases with population-based information on specific genes; 3) commentaries, editorials, and opinion pieces; 4) announcements of conferences, workshops, and training opportunities in human genome epidemiology; 5) funding opportunities in human genome epidemiology; and 6) a forum for communication and dialogue. Public health professionals will be able to use this information to develop intervention and prevention strategies.
Already there is an enormous amount of genetics information available on the Internet and more is added on a daily basis. The resources available range from highly technical reports geared towards geneticists and health-related professionals to information on support groups and organizations for consumers. Most of this information is free and can be viewed by anyone with Internet access. For resources that are not free (e.g., software programs) many provide demonstration files online for preview prior to purchase. Below are examples of some resources that may be useful to public health professionals as well as consumers. Additional WWW resources on genetics are listed in the Appendix.
Medical Genetic Databases
Online Mendelian Inheritance in Man (OMIM T)(6),the Internet version of Mendelian Inheritance in Man, 12th edition (25 ), is a resource first published by Victor A. McKusick, M.D. in 1966. OMIM is maintained by the National Center for Biotechnology Information (NCBI) and is continually updated with information from peer-reviewed journals in genetics, molecular biology, and related disciplines. Mendelian Inheritance in Man/OMIM is considered the most authoritative reference for information on inherited traits. The printed version of McKusick's catalog focuses on single-gene traits (e.g., cystic fibrosis), while the online version also includes chromosomal conditions (e.g., cri-du-chat), as well as multifactorial traits (e.g., Alzheimer disease) (6,25).
OMIM provides a comprehensive description and overview of more than 10,000 genetic conditions. Each listing describes the condition, including clinical features, mode of inheritance, molecular and cytogenetic findings, diagnostic criteria, clinical management, and references. Each OMIM entry is given a unique six-digit number, a McKusick number, whose first digit indicates the mode of inheritance. The presence or absence of an asterisk (*) or number symbol (#) before an entry number provides information about the locus / phenotype / gene relationship. The numbering system also designates allelic variants. If prenatal diagnosis is available for a condition, it is probably mentioned in the molecular genetics or diagnosis section. If there is no information specifically given, this does not mean that prenatal diagnosis is not available, since there may be implied capability of prenatal diagnosis if the DNA mutation is identified or there is known linkage.
GeneClinics (26) is an online resource that contains comprehensive clinical descriptions, diagnostic criteria, management and counseling issues, molecular laboratories, and genetic support group links for specific genetic conditions. It is maintained by certified genetics professionals affiliated with the University of Washington. The disease profiles are written by experts and are peer reviewed. By July 2000, 250 disease profiles will be included. GeneClinics (26) complements GeneTests™ (7), which is a directory of medical genetics laboratories.
Genetic Testing Laboratories
GeneTests™ (7)is an online international directory of clinical and research genetic laboratories and is a valuable resource for locating laboratories offering genetic testing. This database maintains up-to-date information on genetic testing for more than 550 conditions from over 300 laboratories. Access is through user registration. GeneTests™ 7)is overseen by board certified clinical geneticists and genetic counselors at the University of Washington, with support from the National Library of Medicine. GeneTests™ (7) can be searched by gene, laboratory, laboratory director, or OMIM catalog number. The Web site will expand in the future to contain educational material aimed at nongenetics health care providers. This material will include a glossary and sections on the benefits of genetic testing, general uses of genetic testing, indications for referral for a genetics consultation, a genetics clinic directory, components of genetic counseling, and instructions on how to order a genetic test.
Genetic Support Groups
Numerous Internet sites provide information on specific genetic conditions for patients, health care professionals, policy makers, and the general public. Information varies between organizations regarding basic genetics, clinical features, management, treatment, medical advances, references, and community resources. Support groups frequently provide the full-published text of their brochures on their Web sites. Some Web sites focus on specific categories of genetic conditions, such as cancer (Cancer Family Alliance) or deafness (The Heredity Hearing Impairment Resource Registry-NIDCD HHIRR). The Alliance of Genetic Support Groups (27) database maintains current information on support groups for more than 300 genetic and rare conditions. Their Web site is regularly updated to provide accurate addresses, phone numbers, and other valuable information. The Genetic Conditions and Rare Conditions Information (28) Web site links to genetic support groups, educational materials, and research resources. Included are local, national, and international not-for-profit and private support groups.
Professional Genetic Organizations
All the professional genetic organizations have Web sites with information about public policy statements and other pertinent topics. The Web site entitled A World of Genetic Societies (29) contains an overall list of professional genetic organizations. Membership directories may also be accessible from this Web site, as well as information on genetic centers, education programs, and resources. A listing of professional organizations can also be found on the Centers for Disease Control and Prevention's Office of Genomics and Disease Prevention Web site (23).
Information for Genetic Professionals (11) is a Web site overseen by a board-certified genetic counselor at the University of Kansas Medical Center. This site is updated continuously with input from international genetic resources. Included are resources for patient care, research, and education. Links are provided to clinical genetic centers, genome centers, and sites that focus on ethical and legal issues associated with genetics. Updated information about Web resources in this chapter is available at this site.
Although the Internet provides an excellent mechanism of disseminating information, one must be aware that the quality of information on the Internet varies widely; ranging from highly technical professional articles to anecdotal information on a personal home page, newsgroup site, or other public area. Internet information may or may not adhere to the established guidelines, peer- review, indexing, and cataloging standards of published medical literature. However, the quality of genetic information on the Internet continues to improve as governmental agencies, educational institutions, research centers, and clinics add informative materials.
Numerous organizations have published criteria for assessing the quality, reliability, and validity of health information on the Internet (30,31). Criteria include: 1) evaluating the credibility and conflicts of interests (qualifications of the medical advisors or scientific advisory board, Web site owner or sponsor, Web site author and credentials), and 2) evaluating the structure and content of the Web site (site review process, frequency with which the site is updated, attribution of sources, comprehensiveness, accuracy, readability, and dating material). A Web site is more useful if it is easy to find and easy to navigate. The number of other Web sites that link to the site is also a means of estimating the value of the site. Moreover, indications of site utilization can be helpful, but misleading, as site access statistics are not standardized and often difficult to interpret. Most server logs do not distinguish repeated visits to a page by the same individual; therefore, the number of visits to a page cannot be equated with the number of visitors.
An example of a set of principles and ethical guidelines for medical and health information on the Web are set forth by the Health on the Net Code of Conduct (HONcode) (32). The HONcode is displayed on sites that clearly indicate that they 1) provide information about the medical health professional or author, 2) respect medical information privacy, 3) display the last modification date, 4) provide bibliographic references and updated links to other sources, 5) provide scientific references for health treatments and benefits, 6) display the e-mail address of the Web site manager, and 7) provide statements regarding site sponsorship and funding.
Few technological advances have had as much an impact on communication and information dissemination as the Internet. Once used primarily by academic, government, and private research organizations, the Internet is now used by most businesses and schools, and is found in many households. Its ability to distribute up-to-date information rapidly, accurately, and inexpensively makes it the ideal mechanism for disseminating the vast amount of information being generated as a result of the Human Genome Project. In an effort to stay informed and up-to-date, public health professionals are likely to depend on the Internet as a repository for genetics information. The Internet will undoubtedly play a crucial role in disseminating genetics information to public health professionals in the new millennium.
- Collins FS, Patrinos A, Jordan E, et al. New goals for the U.S. Human Genome Project: 1998-2003. Science 1998;282:682-689.
- Hafner K, Lyon M. Where wizards stay up late. New York: Simon & Schuster, 1996.
- Glowniak J. History, structure and function of the Internet. Semin Nucl Med 1998;28:135-44.
- Centers for Disease Control and Prevention. Morbidity and Mortality Weekly Report. World Wide Web URL: http://www.cdc.gov/mmwr
- Doyle DJ, Ruskin KJ, Engel TP. Symposium: A clinician's guide to the Internet. The Internet and medicine: past, present, and future. Yale J Bio Med 1996;69:429-437.
- Online Mendelian Inheritance in Man, OMIM (TM). Center for Medical Genetics, Johns Hopkins University (Baltimore, MD) and National Center for Biotechnology Information, National Library of Medicine (Bethesda, MD), 1999. World Wide Web URL: http://www.ncbi.nlm.nih.gov/omim/.
- GeneTestsTM World Wide Web URL: http://www.genetests.org.
- Sikorski R, Peters R. Genomic medicine. Internet resources for medical genetics. JAMA 1997;278:1212-1213.>
- The Global Health Network.
- Supercourse - Epidemiology, the Internet and Global Health. World Wide Web URL: http://www.pitt.edu/~super1/ .
- Information for Genetic Professionals. World Wide Web URL: http://www.kumc.edu/gec/geneinfo.html.
- University of Pittsburgh Graduate School of Public Health Human Genetics Program. World Wide Web URL: http://www.hgen.pitt.edu/
- University of Michigan Public Health Genetics. World Wide Web URL: http://www.sph.umich.edu/genetics/.
- British Medical Journal. World Wide Web URL: http://www.bmj.com/.
- American Journal of Human Genetics. World Wide Web URL: http://www.journals.uchicago.edu/AJHG/.
- American Journal of Public Health. World Wide Web URL: http://www.ajph.org/
- LaPorte RE, Akazawa S, Hellmonds P, et al. Global public health and the information superhighway. Brit Med J 1994;308:1651-1652.
- New York State Department of Health. Wadsworth Center. World Wide Web URL: http://www.wadsworth.org/.
- Centers for Disease Control and Prevention. World Wide Web URL: http://www.cdc.gov/.
- World Health Organization. World Wide Web URL: http://www.who.int/.
- Online Mendelian Inheritance in Man, OMIM (TM). Johns Hopkins University, Baltimore, MD. MIM Number: *602421: Date last edited: 5/20/1999, World Wide Web URL: http://www.ncbi.nlm.nih.gov/omim/.
- California Department of Health Services Genetic Disease Branch. World Wide Web URL:
- Centers for Disease Control and Prevention. Office of Genomics and Disease Prevention. World Wide Web URL: http://www.cdc.gov/genetics/default.htm.
- Centers for Disease Control and Prevention. Human Genome Epidemiology Network (HuGE Net). World Wide Web URL: http://www.cdc.gov/genetics/hugenet/default.htm.
- McKusick, VA. Mendelian inheritance in man. Catalogs of human genes and genetic disorders (12th edition). Baltimore, MD: Johns Hopkins University Press, 1998.
- GeneClinics. World Wide Web URL: http://www.geneclinics.org/.
- Alliance of Genetic Support Groups. World Wide Web URL: http://www.geneticalliance.org/.
- Genetic Conditions and Rare Conditions Information. World Wide Web URL:
- A World of Genetic Societies. World Wide Web
- Kim P, Eng TR, Deering MJ, et al. Published criteria for evaluating health related Web sites: review. BMJ 199;318:647-649.
- Wyatt JC. Commentary: measuring quality and impact of the World Wide Web. BMJ 1997;314:1879-1881.
- Boyer C, Selby M, Scherrer JR, et al. The health on the net code of conduct for medical and health Web sites. Comput Biol Med 1998;28(5):603-10. World Wide Web URL: http://www.hon.ch/HONcode/Conduct.html
Selected Online Genetic Resources
- Alliance of Genetic Support Groups: Contains current information on support groups for more than 300 genetic and rare conditions. Includes accurate addresses, phone numbers, a printed brochure, a list of addresses, and phone numbers.
- Chromosomal Variation in Man: A Catalog of Chromosomal Variants and Anomalies: Consists of a systematic collection of important citations from the world's literature reporting on all common and rare chromosomal alterations, phenotypes and abnormalities in humans.
- Department of Energy Human Genome Program:Focuses on reaching the goals of the U.S. Human Genome Project in cooperation with the extramural division of the National Human Genome Research Institute of the National Institutes of Health.
- GeneClinics (formerly Genline): Contains comprehensive clinical descriptions, diagnostic criteria, management and counseling issues, molecular laboratories and genetic support group links for specific genetic conditions.
- GeneTestsTM (formerly Helix): An online international directory of clinical and research genetic laboratories that provide genetic testing.
- Genetic Conditions and Rare Conditions Information: Links users to support groups, and educational and research resources.
- Genetic Professional Organization: Provides addresses of and information on international genetics groups.
Web site: http://www.kumc.edu/gec/prof/soclist.html
Web site: http://www.faseb.org/genetics (no longer exists)
- The Human Genome Epidemiology Network (HuGENet™): Provides information on the epidemiologic aspects of human genes.
- Human Cytogenetics Database: Includes cytogenetic data on more than 1,000 chromosome aneuploidies.
- Information for Genetic Professionals: Provides links to clinical, research, and educational resources for genetic counselors, clinical geneticists, and medical geneticists, as well as information on training programs in genetics.
- London Dysmorphology Database (LDDB): Includes a clinical description of more than 3,000 non-chromosomal, multiple congenital anomaly syndromes.
- March of DimesProvides information on specific birth defects or infant health problems, pre-pregnancy, pregnancy, teen pregnancy, newborn care, effect of exposure to drugs and environmental hazards during pregnancy (teratogens), support groups, and genetics.
- National Human Genome Research Institute(NHGRI): Heads the Human Genome Project for the National Institutes of Health.
- NORD (National Organization for Rare Disorders, Inc.): Provides education, advocacy, research, and service for voluntary health organizations serving people with rare disorders and disabilities.
- Office of Genomics and Disease Prevention (OGDP): Provides access to current information about the impact of human genetic research on public health and disease prevention.
- Office of Rare Diseases (ORD): Provides information on more than 6000 rare diseases, including research, scientific and medical publications, as well as patient support groups.
- OMIM (Online Mendelian Inheritance in Man): Catalog of human genes and genetic disorders.
- POSSUM (Pictures of Standard Syndromes and Undiagnosed Malformations): Contains descriptions of more than 2,500 singe gene, chromosomal, skeletal and complex genetic syndromes from the medical literature, as well as from the Genetics Clinic at the Murdoch Institute in Victoria, Australia.
Note: Because of dynamic nature of web, some URLs may have changed.