We have investigated the myelin Po gene on chromosome 1 as a candidate gene in two sporadic cases with Dejerine−Sottas disease or hereditary motor and sensory neuropathy (HMSN) type III. We found different mutations, a cysteine substitution for serine 63 in the extracellular domain and an arginine substitution for glycine 167 in the transmembrane domain. The patients were genetically heterozygous for the normal allele and the mutant allele, which was absent in their parents and in one hundred unrelated, healthy controls. The results strongly suggest that a de novo dominant mutation of the Po gene is responsible for at least some sporadic cases of Dejerine−Sottas disease.
|Number of pages||3|
|Publication status||Published - 1993|