Dejerine−Sottas syndrome associated with point mutation in the peripheral myelin protein 22 (PMP22) gene

Dejerine−Sottas syndrome is a hypertrophic, demyelinating neuropathy which appears to demonstrate autosomal recessive inheritance in most pedigrees. Clinical symptoms are similar but more severe than Charcot−Marie−Tooth disease type 1 (CMT1), of which the major subtype, CMT1 A, results either from duplication of a 1.5−megabase DNA region in chromosome 17p11.2−p12 containing the myelin gene PMP22, or from PMP22 point mutation. Mutational analysis of the PMP22 coding region in two unrelated Dejerine−Sottas patients identified individual missense point mutations present in the heterozygous state. These findings suggest that Dejerine−Sottas syndrome can result from dominant point mutation alleles of PMP22.