There are two forms of CCM: familial and sporadic.
* The familial form is passed from parent to child, and affected individuals typically have multiple cerebral cavernous malformations.
*The sporadic form occurs in people with no family history of the disorder. These individuals typically have only one malformation.
Source:
http://bit.ly/1CdryI2 *The disease was common among Spanish settlers in New Mexico in the 1580s. Since then, it has been passed down through generations. New Mexico has the highest population density of the illness in the United States, and thousands of New Mexico Hispanics may be affected.
Souce:
http://1.usa.gov/1GJsa5Z