AT RISK FOR MS - Clinical Conversion of Female Monozygotic Twins Discordant for CIS/MS

Primary Objective: Determine if the presence of characteristic MS-like lesion(s) on baseline MRI predisposes to CIS/MS in female MZ twins discordant for CIS/MS. Secondary Objective: Define the protein and microarray gene expression profile predictive of conversion to MS/CIS in female MZ twins discordant for CIS/MS. Design and Outcomes: This is a single center, clinical study to determine if the presence of MS-like MRI brain lesions predict the rate of conversion to CIS in female MZ twins discordant for CIS/MS. We will screen and recruit 30 subjects, and begin to follow these subjects annually for a total of 5 years to determine if MR brain scans predict CIS/MS conversion. Interventions and Duration: Subjects will be recruited over 2 years and followed for five years with annual neurological examinations and MR brain scans. Sample Size and Population: 30 female co-twins discordant for CIS/MS will be studied. We predict 72% of the 27% 'at risk' subjects with characteristic MR brain lesions at baseline will convert to CIS within 5 years. We predict only 6% of the 73% 'at risk' subjects without characteristic MR brain lesions at baseline will convert to CIS within 5 years. These data will determine if paraclinical (MRI) evidence of demyelinating disease and specific blood or cerebrospinal fluid proteins predict clinical expression of disease in highly susceptible populations predicts.