The human phenotype with primarily impaired myelination is represented by hypomyelinating leukodystrophies. The most frequent form is Pelizaeus-Merzbacher disease, which is due to alterations in the PLP1 gene encoding the major myelin protein. Another form, Pelizaeus-Merzbacher-like disease, is partly associated with mutations in the GJA12 gene encoding gap junction protein alpha 12, but seems to be heterogeneous. Olig1 and Olig2 are transcription factors in oligodendrocyte development. We postulated that disturbed oligodendroglial maturation could be associated with primary hypomyelination in humans and analyzed the coding sequence of OLIG1 and OLIG2 in 13 patients from 12 unrelated families which were thoroughly characterized with regard to phenotype and magnetic resonance imaging results. From our findings we conclude that mutations in OLIG1 and OLIG2 are not likely to be associated with this subgroup of hypomyelinating disorders.
(c) 2006 Wiley-Liss, Inc.