A Chinese CADASIL family with a rare heterozygous mutation in exon 2 of NOTCH3: A case report

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebrovascular disease caused by the neurogenic locus notch homolog protein 3 (NOTCH3) gene mutation. In recent years, most of the newly reported mutations of CADASIL patients mainly occur in exon 3 to 24, while the cases related to exon 2 mutation are rare, and clinical research data are relatively insufficient. In this study, we have reported a case of a rare heterozygous mutation c.128G>A (p.Cys43Tyr) in exon 2 of NOTCH3 in a 41-year-old Chinese man in the light of relevant literatures. A 41-year-old man who suffered slurred speech for 5 days and right lower limb weakness for 4 days was admitted to our hospital. Magnetic resonance imaging of the head revealed diffuse white matter lesions involving the outer capsular area and bilateral temporal poles. The rare heterozygous mutation c.128G>A (p.Cys43Tyr) in exon 2 of NOTCH3 was identified through molecular genetic testing. The proband was diagnosed as having CADASIL. Meanwhile, the same mutation was detected in 2 other family members III5 and IV9. Atorvastatin calcium tablet (20 mg qd) and aspirin enteric-coated tablet (100 mg qd). The patient was hospitalized for 3 weeks and discharged after his symptoms improved. The heterozygous Cys43Tyr mutation in exon 2 of NOTCH3 is rare. Thus, our case report complements the rare mutation of exon 2 and offers additional clinical data for CADASIL patients.