Prospective Investigation of Multiple Sclerosis in the Three Rivers Region

Inclusion Criteria: * Inclusion criteria for MS patients include: 1. Age 7 years or older 2. Willing and able to provide consent (for \>=18 years) or assent with permission from at least one of the child's parents (for \<18 years) 3. Diagnosis of multiple sclerosis or related disorders, including a first central nervous system demyelinating episode with a positive MRI scan or abnormal MRI scans characteristic of MS but no clinical symptoms of the disease * For healthy controls: 1. Age 7 years or older 2. Willing and able to provide consent (for \>=18 years) or assent with permission from at least one of the child's parents (for \<18 years) 3. No known personal history of multiple sclerosis or related disorders 4. No other chronic diseases 5. Family members, unrelated household controls, or controls from the general population could be eligible There is no exclusion criteria.