Short answer · Medically reviewed summary · Last updated: 2026-05-08
Cerebral Autosomal Dominant Arteriopathy with Sub-Cortical Infarcts and Leukoencephalopathy (CADASIL) is an inherited genetic condition caused by mutations in the NOTCH3 gene. Because it follows an autosomal dominant inheritance pattern, a person with the condition has a 50% chance of passing the pathogenic variant to each of their children. Is CADASIL strictly hereditary? CADASIL is both a genetic and hereditary condition.
Is Cadasil (Cerebral Autosomal Dominant Arteriopathy With Sub-Cortical Infarcts And Leukoencephalopathy) hereditary?
Is Cadasil (Cerebral Autosomal Dominant Arteriopathy With Sub-Cortical Infarcts And Leukoencephalopathy) hereditary? The genetic component explained in plain language, reviewed against medical sources, with patient experiences.
Cerebral Autosomal Dominant Arteriopathy with Sub-Cortical Infarcts and Leukoencephalopathy (CADASIL) is an inherited genetic condition caused by mutations in the NOTCH3 gene. Because it follows an autosomal dominant inheritance pattern, a person with the condition has a 50% chance of passing the pathogenic variant to each of their children.
Is CADASIL strictly hereditary?
CADASIL is both a genetic and hereditary condition. It is "genetic" because it is caused by a specific DNA mutation, and it is "hereditary" because this mutation is passed from parent to child. While nearly all cases are inherited from an affected parent, very rarely, a de novo (spontaneous) mutation can occur, meaning the individual is the first in their family to have the condition.
How is the inheritance of CADASIL defined?
CADASIL is inherited in an autosomal dominant pattern. This means that only one copy of the mutated NOTCH3 gene—inherited from either the mother or the father—is sufficient to cause the disease. Because of this, the condition often appears in multiple generations of a single family. The following list outlines the key genetic facts regarding CADASIL transmission:
- Inheritance Pattern: Autosomal dominant.
- Risk per pregnancy: 50% if one parent carries the NOTCH3 mutation.
- Mutation Location: Typically involves mutations in exons 2–24 of the NOTCH3 gene on chromosome 19.
- Penetrance: Clinical penetrance is considered to be nearly 100% in individuals who reach mid-adulthood.
When is genetic testing for CADASIL recommended?
Genetic testing for CADASIL is performed via molecular genetic analysis of the NOTCH3 gene. It is typically recommended for individuals presenting with recurrent strokes, cognitive decline, or migraines with aura, especially when brain MRI findings show characteristic white matter hyperintensities. Testing is also available for asymptomatic at-risk relatives who wish to understand their own health status.
What is the role of genetic counseling?
Genetic counseling is essential for families affected by CADASIL to discuss the implications of test results, the 50% inheritance risk, and family planning options. Counselors can provide information on reproductive choices, including prenatal diagnosis or preimplantation genetic testing (PGT) for those who wish to avoid passing the NOTCH3 mutation to future generations.
Next steps
- Consult a clinical geneticist to discuss whether testing is appropriate for you or your family members.
- Join our DiseaseMaps.org community to connect with 57 other individuals navigating the realities of CADASIL.
- Request a referral to a neurologist specializing in small-vessel brain diseases.
Medical disclaimer: This information is for educational purposes only and does not replace professional medical advice, diagnosis, or treatment.
References
- NIH Genetic and Rare Diseases Information Center (GARD): CADASIL.
- Orphanet: Cerebral Autosomal Dominant Arteriopathy with Sub-Cortical Infarcts and Leukoencephalopathy.
- OMIM (Online Mendelian Inheritance in Man): NOTCH3 gene entry.
- National Library of Medicine: MedlinePlus Genetics - CADASIL.
