Introduction: Multiple sclerosis (MS) is the neurological non-traumatic disease that produces permanent incapacity in the young people with the greatest frequency. An almost total consensus exists on the implication of environmental and genetic factors in the pathogenesis of the disease. In a considerable percentage of patients, antecedent relatives of other cases of MS exist, who are separated by other healthy relatives sometimes.
Aims: We try to study the familial antecedents of the MS patients, to locate to the healthy members of the family including in the forced line of the possible genetic transmission of the disease and ruling out subclinical involvement by the use of magnetic resonance imaging (MRI).
Patients and methods: We reviewed the familial antecedents of the MS patients followed by the MS Unit of the Service of Neurology of the Hospital Virgen Macarena of Seville. After the accomplishment of their genealogical trees, we identified the cases of familial MS. We locate and practice MRI on the healthy subjects of the family, who are in the genetic line of communication of the disease (obligate carriers).
Results and conclusions: We were able to identify 14 obligate carriers of the gene in 12 of the families. In the MRIs that were done, we found MS-compatible lesions in 10 subjects. These findings confirm the existence of silent forms of the disease, that make difficult the knowledge of the genetic implications in the pathogenesis of the disease.