OBJECTIVE: To elucidate the phenotype, genotype, and MRI findings of Korean 
patients with cerebral autosomal dominant arteriopathy with subcortical infarcts 
and leukoencephalopathy (CADASIL) and mutation carriers.
METHODS: The authors studied 40 members of nine unrelated Korean CADASIL 
families. After genetic analysis of Notch3, clinical and MRI findings were 
correlated in 27 mutation carriers.
RESULT: Notch3 mutation sites were C174R (one family, n = 3), R133C (one family, 
n = 3), R587C (one family, n = 1), R544C (two families, n = 5), and R75P (four 
families, n = 15). The clinical features were typical of CADASIL, but the 
frequency of migraine in the Korean population appears low. MRI abnormalities 
were found in 54% of the mutant carriers, the most common being white matter 
hyperintensities. The prevalence of lacunes and microbleeds increased with 
patient age. Anterior temporal areas were less often involved in subjects with 
R75P mutations than in those where mutations occurred in other sites (p = 0.02). 
Gradient echo imaging identified microbleedings in 33% of mutation carriers (64% 
of those with abnormal MRI), whereas diffusion-weighted MRI showed abnormal 
findings in only one patient. Neurologic disability was related to the number of 
lacunar infarcts and the lesion volume of white matter hyperintensities (p < 
0.001) whereas MMSE score was related to the number of lacunar infarcts (p < 
0.005).
CONCLUSIONS: Although Korean cerebral autosomal dominant arteriopathy with 
subcortical infarcts and leukoencephalopathy (CADASIL) mutation carriers show 
similar clinical and MRI findings, these abnormalities appear less frequently 
than in other populations. Relatively frequent microbleedings on gradient echo 
imaging suggest that treatment should be individualized according to MRI 
findings. The novel mutation of R75P, not involving a cysteine residue, is 
related to less frequent involvement of the anterior temporal area, thus 
broadening the spectrum of CADASIL.