It is a disease of the central nervous system.The symptoms of this disease is myelin (fatty insulating sheathes protecting nerve fibres) becomes damaged and scarred. It affects a person's motor, sensory and even cognitive functions. The causes of Multiple sclerosis are genetic and environmental factors. The impact and symptoms of Multiple sclerosis depends on a person's ability to participate in everyday activities different from person to person.
A sample of 337 patients was studied; 99.1% were mestizos, with an average age of 37 9 years, 69.7% were females and 30.3% males. 95% had access to the Social Security system and 96% had been born in Mexico to Mexican parents. No cases were found among native Mexicans. The clinical profile of the disease did not differ to that reported in other countries; the pattern observed corresponded to that found in northern.