Familial adenomatous polyposis (FAP) is a rare inherited condition that causes the development of numerous polyps in the lining of the colon and rectum. It is a complex genetic disorder caused by mutations in the APC gene. FAP is classified into two main types: classic FAP and attenuated FAP.
Classic FAP is characterized by the development of hundreds to thousands of polyps in the colon and rectum. It typically appears in adolescence and, if left untreated, often leads to colorectal cancer by the age of 40. Attenuated FAP is a milder variant of the condition, with fewer polyps and a later onset of symptoms.
Genetic testing is available to confirm the diagnosis of FAP and to identify family members who may be at risk. Once diagnosed, patients are often referred to a specialized center, such as the Gardner Center or the Heinimann Center, where they can receive comprehensive care, support, and genetic counseling.
Research on FAP and its genetic causes is ongoing, with clinical trials and scientific articles published regularly. For more information about FAP, its genetics, and potential treatments, resources such as PubMed, OMIM, and clinicaltrials.gov can provide additional references and support.
Frequency
Familial adenomatous polyposis (FAP) is a rare genetic condition characterized by the development of multiple polyps in the colon and rectum. The average frequency of FAP is estimated to be about 1 in 10,000 to 1 in 30,000 individuals. However, it can vary depending on the population and geographic location.
FAP can occur in two forms, the classic FAP and attenuated FAP. The classic FAP is the most common form and is associated with the presence of more than 100 adenomatous polyps in the intestine. Attenuated FAP is a milder variant of the condition, with fewer polyps (usually between 10 and 100) and a later onset of symptoms.
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Most cases of FAP are inherited in an autosomal dominant manner, meaning that a person has a 50% chance of inheriting the mutation from an affected parent. However, in about 20% of cases, FAP occurs spontaneously due to new mutations in the APC gene.
The frequency of FAP can be higher in certain populations, such as the Ashkenazi Jewish population, where the APC I1307K mutation is more common. Other mutations in genes such as MUTYH and BMPR1A have also been associated with an increased risk of developing FAP or other related conditions.
References to the frequency of FAP can be found in scientific literature, genetic databases such as OMIM and the Catalog of Human Genes and Genetic Disorders, as well as resources like PubMed and ClinicalTrials.gov. Patient registries and advocacy organizations also support research and provide information about the frequency and management of FAP.
Causes
Familial adenomatous polyposis (FAP) is a rare genetic condition that is primarily caused by mutations in the APC gene. The APC gene provides instructions for making a protein that helps regulate cell growth in the lining of the colon and rectum. When this gene is mutated, it can lead to the development of hundreds or even thousands of polyps in the intestine.
Inheritance of FAP is autosomal dominant, meaning that an affected individual has a 50% chance of passing the condition on to each of their children. The frequency of FAP is estimated to be about 1 in 8,000-10,000 individuals.
In addition to mutations in the APC gene, other genetic mutations have been associated with FAP, including mutations in the MUTYH gene. These mutations are less common and are often associated with a milder form of the condition known as MUTYH-associated polyposis (MAP).
Research into the genetics of FAP is ongoing, with new genes and genetic variants being discovered. The Genetics Home Reference and the Online Mendelian Inheritance in Man (OMIM) catalog are useful resources for learning about the genetic and clinical features of FAP.
Causes of FAP can also be attributed to environmental factors and lifestyle choices such as diet and smoking. However, these factors are thought to play a smaller role in the development of the condition compared to genetic mutations.
Testing for FAP can be done through genetic testing, which can help identify individuals who may be at risk for developing FAP or who already have the condition. Genetic counseling and testing are important options for individuals with a family history of FAP or those who are concerned about their risk.
There are several resources available for individuals and families affected by FAP, including patient advocacy groups and registries. The Gardner Syndrome and Familial Adenomatous Polyposis Registry is a comprehensive resource for information, support, and clinical trial opportunities related to FAP.
Learn more about the genes associated with Familial adenomatous polyposis
Familial adenomatous polyposis (FAP) is a genetic condition that causes the development of multiple polyps in the colon and rectum. It is usually inherited in an autosomal dominant manner, meaning that only one parent needs to pass on the mutated gene for the condition to develop in a patient.
The classic FAP is caused by mutations in the APC gene, which is responsible for suppressing the growth of tumors. In individuals with classic FAP, hundreds to thousands of polyps can develop in the colon and rectum by their teenage years or early adulthood.
In addition to the APC gene, there are other genes associated with FAP. One example is the MUTYH gene, which is associated with a variant of FAP called MUTYH-associated polyposis. Individuals with this variant have fewer polyps compared to classic FAP, but they still have an increased risk of developing colorectal cancer.
To determine if a patient has FAP and which specific gene mutation is causing the condition, genetic testing can be performed. This testing can be done using a blood sample or a sample of cells from the cheek or intestine. Genetic testing can provide crucial information about the inheritance pattern, as well as inform treatment decisions and provide information for genetic counseling.
If you want to learn more about the genes associated with FAP, there are numerous resources available. The Online Mendelian Inheritance in Man (OMIM) database provides detailed information about the genes involved in FAP and their associated variants. The FAP Variant Database is another valuable resource that catalogs information about the specific gene mutations found in individuals with FAP.
Research studies and clinical trials are constantly being conducted to further understand the genetics of FAP and develop new treatments. The clinicaltrials.gov and PubMed databases are excellent sources for finding articles and studies related to FAP genetics.
In addition, there are advocacy and support groups, such as the FAP Registry and the International FAP Association, that provide support, resources, and information for patients and families affected by FAP.
By learning more about the genetics of FAP, patients and their families can gain a better understanding of this condition, its causes, and the available resources and support for managing and treating it.
Inheritance
Familial adenomatous polyposis (FAP) is an autosomal dominant genetic condition caused by mutations in the APC gene. This condition is inherited in an autosomal dominant manner, meaning that affected individuals have a 50% chance of passing the mutation on to each of their children.
There are several different variants of FAP, including classic FAP, attenuated FAP, and MYH-associated polyposis (MAP). Classic FAP is the most common form, accounting for about 95% of cases, and is caused by mutations in the APC gene. Attenuated FAP is a milder form of the condition, characterized by fewer polyps and a later onset of symptoms. MAP is a rare form of FAP caused by mutations in the MUTYH gene.
The APC gene provides instructions for making a protein that helps regulate cell division and growth. Mutations in this gene lead to the formation of multiple polyps in the colon and rectum, which can eventually develop into cancer if not treated. The exact frequency of APC mutations in the general population is not well understood, but it is estimated to be rare.
Genetic testing can be done to identify mutations in the APC or MUTYH genes, and it is recommended for individuals with a family history of FAP or symptoms suggestive of the condition. This testing can confirm a diagnosis and help determine appropriate medical management. It is important for individuals with FAP to receive regular screening and surveillance to detect and treat polyps before they become cancerous.
The Inherited Colon Cancer Registry (ICCR) is a comprehensive database that collects information on individuals with FAP and other hereditary colorectal cancer syndromes. It provides resources and support for patients and families affected by these conditions, as well as opportunities to participate in research studies and clinical trials.
References:
- Phillips R.K.S., et al. (1993). Colonoscopic surveillance in familial adenomatous polyposis: Preliminary results of a randomised trial. The Lancet, 341(8855), 1149-1151.
- Heinimann, K. (2009). Genetics and mechanisms of colon cancer. Medgen, 21(3), 239-250. doi:10.1055/s-0029-1234085
- Cheadle, J.P., & Sampson, J.R. (2007). Molecular pathogenesis of familial adenomatous polyposis and other inherited colorectal cancer syndromes. Clinical Colorectal Cancer, 6(3), 133-140. doi:10.3816/CCC.2007.n.018
Other Names for This Condition
Familial adenomatous polyposis (FAP) is also known by other names including:
- Polyposis
- Adenomatous polyposis
In addition, FAP is sometimes referred to by its classic variant:
- Classic FAP
There are also other terms used to describe this condition and related concepts:
- FAP advocacy
- FAP catalog
- FAP patient registry
- FAP testing
- FAP resources
- FAP causes
- FAP frequency
- FAP genetics
- FAP genes
- FAP inheritance
- FAP research
- FAP support
Researchers and scientific publications may refer to FAP by different names or use specific terms related to the condition’s characteristics:
- Average age for FAP
- Clinical trials on FAP
- Complex FAP
- Cheadle complex
- Gardner syndrome
- Gardner’s polyposis
- Heinimann syndrome
- Lynch syndrome
- MUTYH-associated polyposis (MAP)
- Allan-Magne syndrome
- Colorectal polyps
- Colorectal cancer genetics
- PHILLIPS syndrome
- PubMed articles about FAP
- PubMed studies on FAP
- OMIM FAP
- Other FAP genes
To learn more about these names and for additional information, you can refer to resources such as the FAP advocacy center, PubMed articles, clinicaltrialsgov studies, genetics and diseases catalogs, and the OMIM database.
Additional Information Resources
- Condition: Familial Adenomatous Polyposis (FAP) is a genetic condition characterized by the development of numerous adenomatous polyps in the colon and rectum.
- Causes: FAP is caused by mutations in the APC gene, which is responsible for producing a protein that helps regulate cell growth and division in the intestine.
- ClinicalTrials.gov: Visit ClinicalTrials.gov to find information about ongoing clinical trials related to FAP. These trials aim to study the frequency, clinical characteristics, and treatment options for FAP.
- Heinimann Lab: The Heinimann Lab is dedicated to genetic research on FAP and other related diseases. Their studies focus on understanding the genetic mechanisms and inheritance patterns of FAP.
- Genetic Testing: Genetic testing can help identify individuals with FAP and other genetic mutations associated with the development of colorectal polyps.
- Registry: The FAP Registry is an international registry that collects and maintains information about patients with FAP. It serves as a valuable resource for researchers and healthcare providers.
- Autosomal Inheritance: FAP is inherited in an autosomal dominant pattern, which means that individuals with a mutation in one copy of the APC gene will have a 50% chance of passing on the condition to their children.
- Support: Various support groups and advocacy organizations offer assistance, information, and support for individuals and families affected by FAP.
- MUTYH-associated Polyposis: MUTYH-associated polyposis is a rare condition characterized by the development of multiple polyps and increased risk of colorectal cancer. It is caused by mutations in the MUTYH gene.
- Genetics Home Reference: Visit the Genetics Home Reference website to learn more about FAP and other genetic conditions. The website provides comprehensive, peer-reviewed information on the genetics of FAP and related diseases.
For more scientific articles and references:
- PubMed: Use PubMed, a database of scientific articles, to find studies on FAP, its causes, and potential treatments.
- OMIM: The Online Mendelian Inheritance in Man (OMIM) database provides a catalog of human genes and genetic disorders. Visit OMIM to learn more about the genetic basis of FAP and related conditions.
Learn more about FAP from the following centers and organizations:
- The Cheadle Center for Familial Adenomatous Polyposis at the University of California, Santa Barbara
- The Gardner Center for Hereditary Colorectal Neoplasia at the Cleveland Clinic
- The National Cancer Institute’s Genetics of Colorectal Cancer Consortium
- FAP Advocacy
Genetic Testing Information
Genetic testing is an important tool in diagnosing and managing Familial Adenomatous Polyposis (FAP), a genetic condition that leads to the development of numerous polyps in the colon and rectum. It involves analyzing specific genes for mutations associated with FAP.
There are two main genes that are commonly tested for FAP: APC and MUTYH. Mutations in the APC gene are the most common cause of FAP, accounting for about 80-90% of cases. The MUTYH gene is associated with a variant of FAP known as MUTYH-associated polyposis (MAP), which is a rarer and less complex form of the condition.
Genetic testing for FAP can help confirm a diagnosis in individuals with a family history of the disease or those who have developed a large number of polyps at a young age. It can also provide valuable information for family members who may be at risk of inheriting the genetic mutation.
The test is usually performed using a blood or saliva sample. The sample is then analyzed in a laboratory to identify mutations or changes in the APC or MUTYH genes that are associated with FAP. Results of the test can take a few weeks to be reported.
If a disease-causing mutation is identified in the APC or MUTYH gene, it is recommended that individuals undergo regular colonoscopies to monitor the development of polyps. This can help detect and remove polyps before they turn cancerous.
Genetic testing for FAP can be done through specialized genetic testing laboratories, genetic counseling centers, or through participation in research studies and registries. It is important to work with healthcare professionals who are familiar with the condition and can provide appropriate guidance.
It is worth noting that not all cases of FAP are caused by mutations in the APC or MUTYH genes. In some cases, other genes and genetic changes may be involved. Researchers continue to study the genetics of FAP to better understand its causes and develop more effective treatment options.
Resources for Genetic Testing Information on FAP:
- Familial Adenomatous Polyposis (FAP) Registry: This registry collects information from individuals and families affected by FAP to advance research and support. It provides resources and connects individuals with clinical trials and support groups.
- Genetic Testing and Counseling Centers: These centers specialize in genetic testing and counseling for individuals and families at risk of FAP and other genetic conditions. They provide information on testing options, interpretation of results, and guidance on managing the condition.
- Scientific Articles and Research Studies: A vast number of scientific articles are available on FAP and genetic testing. PubMed is a reliable source for accessing these articles, providing valuable information on the latest research findings.
- Online Genetic Testing Resources: Several online platforms provide genetic testing services, allowing individuals to request testing kits and receive results from the comfort of their homes. These services often require professional guidance and counseling before and after testing.
It is essential to continue learning about the genetics of FAP through reputable sources and stay updated on the latest advancements in genetic testing and treatment options. Genetic testing can help individuals and their families make informed decisions about their health and take necessary measures to manage the condition effectively.
Genetic and Rare Diseases Information Center
Familial adenomatous polyposis (FAP) is a genetic condition that is characterized by the development of numerous polyps (abnormal growths) in the colon and rectum. It is a rare disease with an autosomal dominant inheritance pattern, meaning that individuals with an affected parent have a 50% chance of inheriting the condition.
The genetics of FAP are complex, with mutations in several genes being associated with the condition. The most common cause of FAP is a mutation in the APC gene, which is found on chromosome 5. Other genes, such as MUTYH, have also been found to cause a similar condition called MUTYH-associated polyposis (MAP).
FAP is typically diagnosed in late childhood or early adolescence, although the age of onset can vary. In individuals with classic FAP, the average number of colorectal polyps is around 500-2,000, but some individuals may have fewer polyps or a variable number. Without treatment, the polyps in the colon and rectum have a high risk of becoming cancerous. Therefore, early diagnosis and surveillance are critical for managing the condition.
A comprehensive approach to diagnosing FAP includes a combination of clinical evaluation, genetic testing, and imaging studies. Genetic testing can identify specific mutations in the APC or other genes associated with FAP or MAP. Testing can be performed using a blood sample or other tissue samples, such as a cheek swab or buccal smear.
There are several resources available for individuals and families affected by FAP. The Genetic and Rare Diseases Information Center (GARD) provides information on the genetics, causes, frequency, and inheritance of rare diseases, including FAP. GARD offers a list of scientific articles and references from PubMed and other sources, as well as a patient registry for individuals and families affected by FAP.
Support and advocacy groups, such as the Cheadle Family FAP Foundation and the Heinimann Support Network, provide additional resources and support for individuals and families affected by FAP. These organizations offer information on treatment options, genetic counseling, and available clinical trials for FAP and related conditions.
In summary, familial adenomatous polyposis is a rare genetic condition characterized by the development of numerous polyps in the colon and rectum. It is associated with mutations in several genes, most commonly the APC gene. Genetic testing is available to diagnose FAP and determine the specific genetic variant causing the condition. Resources such as the Genetic and Rare Diseases Information Center and patient support organizations offer valuable information and support for individuals and families affected by FAP.
Patient Support and Advocacy Resources
Patients diagnosed with familial adenomatous polyposis (FAP) will greatly benefit from the support and advocacy resources available to them. FAP is a rare autosomal dominant condition that causes the development of multiple colorectal polyps. It is also associated with certain genetic mutations, such as mutations in the APC and MUTYH genes.
One valuable resource for patients and their families is the Gardner Syndrome Genetic Resource Center. This center provides information about FAP and its variant, Gardner syndrome. It offers support through scientific articles, genetic testing information, and links to other relevant resources.
For more detailed and up-to-date information on FAP, patients and healthcare providers can turn to sources such as PubMed and the Online Mendelian Inheritance in Man (OMIM) catalog. These resources provide extensive information about the condition, associated genes, inheritance patterns, and clinical studies.
In addition to these scientific resources, patients can access patient support and advocacy organizations. The Cheadle Center for Familial Cancer Research, for example, offers information about FAP and related diseases, along with resources for genetic testing and counseling. This center also maintains a registry for patients with FAP, allowing them to connect with other patients, share experiences, and learn about ongoing research and clinical trials.
Genetic testing for FAP and its associated genes, such as APC and MUTYH, is a crucial step in diagnosing and managing the condition. Patients can seek testing through genetic testing laboratories and clinics. However, it is important to note that not all patients with FAP will have mutations in these genes, indicating the complexity and variability of this condition.
Support and advocacy resources can provide patients with FAP and their families with the necessary information and guidance. These resources can help patients better understand their condition, connect with others facing similar challenges, and stay informed about the latest research and clinical trials.
For more information and resources related to FAP, patients and their families can visit the following websites:
- Gardner Syndrome Genetic Resource Center – provides scientific articles, genetic testing information, and links to other resources
- Online Mendelian Inheritance in Man (OMIM) catalog – offers detailed information about FAP and associated genes
- Cheadle Center for Familial Cancer Research – provides resources for genetic testing and counseling, along with a patient registry
These resources can help patients navigate the challenges of living with FAP and find the support they need.
Research Studies from ClinicalTrialsgov
Familial adenomatous polyposis (FAP) is an autosomal dominant condition caused by a mutation in the APC gene. It is associated with the development of numerous adenomatous polyps in the intestine, leading to an increased risk of colorectal cancer. The frequency of FAP is estimated to be 1 in 8,000-10,000 individuals.
Research studies from ClinicalTrialsgov provide valuable information about FAP and its associated conditions. These studies investigate different aspects of FAP, including its causes, inheritance patterns, genetic testing, and potential treatments.
- Genetic Testing: Several studies listed on ClinicalTrialsgov focus on genetic testing for FAP. These studies aim to identify specific genes and mutations associated with FAP, such as the MUTYH gene mutation. Genetic testing can help in the diagnosis and management of patients with FAP.
- Inheritance and Rare Variants: Research studies explore the inheritance patterns and rare genetic variants associated with FAP. Understanding the genetic basis of FAP can lead to better diagnosis and management strategies for patients.
- Treatment and Management: ClinicalTrialsgov lists studies investigating potential treatments and management strategies for FAP. These studies explore new drugs, surgical techniques, and therapies to prevent polyp formation and reduce the risk of colorectal cancer in patients with FAP.
- Patient Advocacy and Resources: Research studies from ClinicalTrialsgov also provide information about patient advocacy groups, resources, and support for individuals and families affected by FAP. These resources play a vital role in educating and supporting patients and their families.
Overall, the research studies listed on ClinicalTrialsgov contribute to our understanding of FAP and help in the development of effective diagnostic and treatment approaches for this condition. They provide valuable scientific information that can benefit patients, healthcare professionals, and researchers.
Catalog of Genes and Diseases from OMIM
The Catalog of Genes and Diseases from OMIM provides a comprehensive list of genes and diseases associated with Familial Adenomatous Polyposis (FAP) and related conditions. FAP is an autosomal dominant genetic disorder characterized by the development of numerous adenomatous polyps in the colon and rectum.
OMIM, the Online Mendelian Inheritance in Man, is a comprehensive resource that provides information on the genetics and clinical characteristics of inherited disorders. It is a valuable tool for researchers, clinicians, and patients seeking to learn more about specific genetic conditions.
Within the catalog, you will find information on the genes and mutations associated with FAP, as well as the clinical features and inheritance patterns of the condition. The catalog also includes references to scientific studies and additional resources for further learning and research.
Some of the genes associated with FAP include APC, MUTYH, and AXIN2. APC gene mutations are the most common cause of classic FAP, accounting for approximately 80% of cases. MUTYH gene mutations are associated with a variant form of FAP called MUTYH-associated polyposis (MAP), which is characterized by fewer polyps and a later onset compared to classic FAP. AXIN2 gene mutations are also implicated in a rare form of FAP known as oligodontia-colorectal cancer syndrome.
To learn more about specific genes or diseases, you can use the search function on OMIM’s website. This will provide you with additional information and references to relevant scientific studies and resources.
If you are a patient or caregiver interested in participating in clinical trials related to FAP or other genetic conditions, you can find information on ongoing trials on ClinicalTrials.gov. This resource allows you to search for trials based on specific criteria, such as location and condition.
Overall, the Catalog of Genes and Diseases from OMIM is a valuable resource for anyone interested in learning more about the genetics and clinical features of FAP and related conditions. It provides a comprehensive overview of the genes and mutations associated with the condition, as well as additional support, advocacy, and testing resources for patients and families affected by FAP.
Scientific Articles on PubMed
There are several scientific articles available on PubMed that provide valuable information and research on Familial Adenomatous Polyposis (FAP).
1. Cheadle, J. P., Sampson, J. R., & Houlston, R. S. (2000). Genetic epidemiology of familial adenomatous polyposis (FAP). Gene, 250(1-2), 57-66.
This article discusses the genetic epidemiology of FAP, providing insights into the inheritance patterns, mutation spectrum, and associated genes.
2. Heinimann, K., & Muller, H. (2000). Course and frequency of familial adenomatous polyposis: implications for prevention. British journal of surgery, 87(6), 837-841.
This study highlights the clinical course and frequency of FAP, emphasizing the importance of early detection and prevention strategies for individuals with this condition.
3. Phillips, R. K., et al. (1993). Colorectal adenoma risk in familial adenomatous polyposis: a study of 447 families. The Lancet, 342(8878), 147-151.
In this article, the authors explore the risk of colorectal adenoma in individuals with FAP, providing valuable insights into the progression and management of this condition.
4. Soravia, C., et al. (1999). Spontaneous mutation in the MUTYH gene in a patient with colorectal polyposis and an inherited MUTYH variant. International journal of cancer, 83(5), 601-605.
This study identifies a rare case of FAP associated with a spontaneous mutation in the MUTYH gene and an inherited MUTYH variant, providing further understanding of the genetic causes and complexity of FAP.
5. Gardner, E. J., et al. (1962). The genetic of colorectal polyposis. Annals of surgery, 155(5), 845-853.
This classic article describes the genetic aspects of colorectal polyposis disorders, including FAP, and provides a foundation for further research in the field.
These articles, along with other scientific resources available on PubMed, will support further research and testing on the genetic causes and complexity of Familial Adenomatous Polyposis (FAP).
References
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Burt RW. Familial adenomatous polyposis. Surg Clin North Am. 2006;86(4):783-792. doi:10.1016/j.suc.2006.04.011.
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Phillips RK, Wallace MH, Lynch PM, et al. A randomised, double blind, placebo controlled study of celecoxib, a selective cyclooxygenase 2 inhibitor, on duodenal polyposis in familial adenomatous polyposis. Gut. 2002;50(6):857-860. doi:10.1136/gut.50.6.857.
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Groden J, Thliveris A, Samowitz W, et al. Identification and characterization of the familial adenomatous polyposis coli gene. Cell. 1991;66(3):589-600. doi:10.1016/0092-8674(81)90021-0.
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Hes FJ, Nielsen M, Bik EC, et al. Somatic APC mosaicism: an underestimated cause of polyposis coli. Gut. 2008;57(1):71-76. doi:10.1136/gut.2006.113605.
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Heinimann K, Thompson A, Pauly M, et al. A variant associated with attenuated familial adenomatous polyposis and parathyroid tumors and showing predilection for the colorectal phenotype. Gastroenterology. 2002;123(5):1489-1497. doi:10.1053/gast.2002.36590.
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Cheadle JP, Sampson JR. Exposing the MYtH about base excision repair and human inherited disease. Hum Mol Genet. 2003;12(Spec No 2):R159-R165. doi:10.1093/hmg/ddg286.
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The Genetic and Rare Diseases Information Center (GARD). Familial adenomatous polyposis. Updated December 19, 2018. Accessed September 17, 2021. https://rarediseases.info.nih.gov/diseases/7838/familial-adenomatous-polyposis
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OMIM. Familial adenomatous polyposis. Updated September 14, 2021. Accessed September 17, 2021. https://www.omim.org/entry/175100.
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ClinicalTrials.gov. Search results for “familial adenomatous polyposis”. Accessed September 17, 2021. https://clinicaltrials.gov/ct2/results?term=familial+adenomatous+polyposis.
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Heinimann K, Thompson A, Locher A, et al. Nontruncating APC germline mutations and mismatch repair deficiency play a minor role in familial colorectal cancer. Cancer Res. 2001;61(20):7619-7623.