CHARCOT-MARIE-TOOTH-DISEASE - MOLECULAR CHARACTERIZATION OF PATIENTS FROM CENTRAL AND SOUTHERN ITALY

The syndrome of peroneal muscular atrophy, or Charcot-Marie-Tooth (CMT ), disease represents the most common inherited peripheral neuropathy, with a prevalence of about 1 per 2500. The disease is usually transmi tted in an autosomal dominant fashion, although it can display all the mendelian patterns of inheritance. The chromosome 17-linked form (CMT 1a) appears to be the most common form of the disease in all the ethni c groups studied so far, Italians included, and is due to a tandem dup lication in 17p11.2. In order to study the distribution of CMT types a nd to establish a genotype-phenotype correlation in patients from Cent ral and Southern Italy, we collected 19 CMT pedigrees diagnosed in the years 1992-1993. Simple tandem repeats (STR) polymorphism analysis wi th the marker RM11-GT and Southern blotting with the probes pVAW409R3 and pVAW412 were performed, demonstrating a high prevalence (about 60% ) of 17p duplication in the families studied. No clinical or electroph ysiological differences were noted between CMT1 patients with or witho ut 17p duplication, respectively. Two families affected by CMT2 showed no evidence of rearrangement at the D17S122 locus. These data are con sistent with the hypothesis of a different molecular basis for CMT2.