The objective of the study was to investigate a girl with giant axonal 
neuropathy and detect the mutation of GAN gene in her family. The encoding exons 
of GAN gene were amplified from genomic DNA of the proband and her parents by 
polymerase chain reaction and directly sequenced after purification. The proband 
manifested typical neurological symptoms and pathological abnormalities. The 
case had 2 heterozygous missense mutations in GAN gene: 1. c. 224 T>A in exon 2, 
her mother was a heterozygote of this mutation and had normal phenotype; 2. 
c.1634G>A in exon 10, and her father was a heterozygote of this mutation and had 
normal phenotype. Both of the mutations caused amino acid changes in the 
gigaxonin protein. In this family, missense mutation of c.224 T>A and missense 
mutation of c.1634G>A in GAN gene caused the phenotype of giant axonal 
neuropathy in the proband. Her parents are heterozygotes of the disease without 
symptoms.