THE VALUE OF FAMILY INVESTIGATIONS IN NEWLY DETECTED CHARCOT-MARIE-TOOTH DISEASE IN CHILDREN

Charcot-Marie-Tooth disease (CMT) was diagnosed by nerve conduction ve locity and histology of the sural nerve in two boys aged 3 and 6 years with clinical signs of a severe neuromuscular disease. DNA analysis r evealed the typical duplication on chromosome 17p11.2 (2.7 kb allele) for CMT 1A. Although none of their family members reported symptoms of neuromuscular disease, the nerve conduction velocity was reduced in t hree members (father and two aunts). They were homozygous for the 2.7 kb allele and were assumed to carry three copies of this allele. The v ery differing clinical picture from one generation to the next in pati ents with identical neurophysiological and genetic results is discusse d.