Cerebral cavernous malformation
- Cavernous angioma
- Cerebral cavernous hemangioma
Your QuestionMy husband had a bleed 20 yrs ago and has multiple cerebral cavernous malformations (CCM). My son had a bleed and was also diagnosed with multiple CCMs. Does our family need genetic testing?
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Questions on this page
- What are cerebral cavernous malformations (CCMs)?
- What causes cerebral cavernous malformations?
- What are the signs and symptoms of cerebral cavernous malformations?
- Are cerebral cavernous malformation inherited?
- Is genetic testing available for cerebral cavernous malformation (CCM)?
- If there are multiple individuals in a family with cerebral cavernous malformations, should family member's at risk consider genetic testing?
Most CCMs are caused by a mutation in one of three particular genes i.e. KRIT1, CCM2, and PDCD10. The gene mutation may occur for the first time the affected indiviudal (sporadic) or be inherited from a parent (familial). Acquired CCM can be cause by an injury to the brain or spinal cord. 
Individuals with sporadic CCM did not inherit the mutation from a parent. As mentioned above, they typically have only one or two CCM and have no family members with CCMs. The CCM developed from a gene mutation that occurred after conception and is not present in all cells of their body. Those with sporadic CCM do not have a greater chance of having a child with CCM than anyone else in the general population (1 in 200), because the mutation is not located in the reproductive cells. 
Familial CCM is inherited in an autosomal dominant manner which means one copy of the altered gene in each cell is sufficient to cause the disorder. The proportion of familial cases has been estimated to be as high as 50% in Hispanic individuals and 10-40% in Caucasian individuals. Families with familial CCM typically have (1) multiple lesions on cerebral MRI and (2) several affected individuals in more than one generation. However, not everyone who has an altered gene for CCM develops symptoms. The occurrence of CCMs that are not symptomatic may prevent recognition of an autosomal dominant pattern of inheritance in a family. Additionally, individuals with multiple CCMs may not have a family history of CCM. In those cases, the mutation could have occured for the first time (de novo mutation) in that individual.
Each child of an individual with familial CCM has a 50% chance of inheriting the mutation. 
You can find a list of laboratories that provide genetic testing for CCM through the Genetic Testing Registry (GTR). The GTR is a centralized online resource for information about genetic tests. The intended audience is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.
Genetic testing can not be performed on a blood sample from someone with sporadic CCM becuase the gene mutation may be located in tissues other than the blood.
To learn more about genetic testing for your family, we recommend that you speak with a genetic professional. Genetics services are a source of information for individuals and families regarding genetic diagnosis, natural history, treatment, mode of inheritance, and genetic risks to other family members. To find a genetics service near you, we recommend that you contact your primary doctor for a referral. Click here to learn more about genetic consultations.
The following online resources can also help you find a genetics professional in your community:
* GeneTests - A searchable directory of US and international genetics and prenatal diagnosis clinics. Go to the following link and click on 'Clinic Directory' to find a genetic service close to you. http://www.geneclinics.org/
* ResourceLink - A database of genetics counseling services, searchable by location, name, institution, type of practice, or specialty. Hosted by the National Society of Genetic Counselors.
* Genetic Centers, Clinics, and Departments - A comprehensive resource list for genetic counseling, including links to genetic centers and clinics, associations, and university genetics departments. Hosted by the University of Kansas Medical Center. http://www.kumc.edu/gec/prof/genecntr.html
- Cerebral cavernous malformation. Genetics Home Reference. November 2012; http://ghr.nlm.nih.gov/condition/cerebral-cavernous-malformation. Accessed 12/5/2012.
- Akers, Amy Ph.D.. Cavernous Malformation. National Organization for Rare Disorders (NORD). 2010; http://www.rarediseases.org/rare-disease-information/rare-diseases/byID/620/viewAbstract. Accessed 12/5/2012.
- NINDS Cerebral Cavernous Malformation Information Page. National Institute of Neurological Disorders and Stroke (NINDS). 2007; http://www.ninds.nih.gov/disorders/cavernous_malformation/cavernous_malformation.htm. Accessed 8/12/2009.
- Riant, Florence et.al.. Recent insights into cerebral cavernous malformations:the molecular genetics of CCM. FEBS Journal. 2010;
- Morrison L, Akers A. Cerebral Cavernous Malformation, Familial. GeneReviews. May 2011; http://www.ncbi.nlm.nih.gov/books/NBK1293/. Accessed 12/5/2012.