[Sporadic and familial-occurring multiple sclerosis. HLA typing and study of chromosomal sister chromatid exchange rate].

HLA and sister chromatid exchange (SCE) has been investigated in 17 multiple sclerosis cases and 10 controls. While the HLA showed no differences between familial cases of MS and the control group, in sporadic cases of MS the occurrence of the antigen A3 and B7 have been confirmed. The study showed a significant increase of the SCE-rate in sporadic cases of multiple sclerosis, in the contrary, in those cases with familial occurrence no changes in the SCE-rate could be found. A different etiology for sporadic and familial cases of multiple sclerosis is assumed.