GENETIC SUSCEPTIBILITY TO MULTIPLE-SCLEROSIS IN THE SHANGHAI CHINESE IS NOT LINKED TO THE MYELIN BASIC-PROTEIN GENE MICROSATELLITE

Aim-To investigate the role of myelin basic protein (MBP) gene polymor phisms in determining susceptibility to multiple sclerosis in a Shangh ai Chinese population. Methods-Forty seven unrelated patients with mul tiple sclerosis and 94 healthy control subjects were included in the s tudy. Genomic DNA was extracted from peripheral blood lymphocytes and amplified using the polymerase chain reaction to characterise two adja cent tetranucleotide repeats ([ATGG](12) and [TGGA](9)) located 5' to exon 1 of the MBP gene. Results-Two polymorphic loci were identified: locus A, comprising both repeats, and locus B, comprising the [ATGG](1 2) repeat only. Nine allelic variants were identified at locus A and s ix at locus B, ranging from 212 to 244 and 122 to 146 base pairs, resp ectively. The 244 base pair allele at locus A has not been reported be fore. The allele frequencies observed in the controls differed from th ose seen in normal white populations. Conclusions-The present study de monstrates a race specific pattern of allelic distribution within the tetranucleotide repeat of the MBP gene. Further studies are needed to fully elucidate the role of the MBP gene in inherited susceptibility t o multiple sclerosis.