Two novel mutations in the GAN gene causing giant axonal neuropathy

Area of Science:

• Genetics
• Neuroscience
• Molecular Biology

Background:

• Giant axonal neuropathy (GAN) is a rare, autosomal recessive neurodegenerative disorder.
• It manifests in early childhood with motor and sensory deficits, leading to severe disability and premature death.
• Mutations in the GAN gene, encoding the gigaxonin protein, are implicated, but the precise molecular mechanisms remain unclear.

Observation:

• The study reports the first documented case of GAN in a Mexican patient.
• Genetic sequencing identified compound heterozygous novel mutations in the GAN gene.
• These mutations were located in the Kelch repeats domain of the gigaxonin protein.

Findings:

• Two distinct missense mutations, C>T at g.55393 and G>T at g.67471, were identified in the patient's GAN gene.
• Bioinformatic tools predicted a detrimental impact of these mutations on gigaxonin protein function and structure.
• The patient presented with clinical features consistent with GAN.

Implications:

• This research expands the known spectrum of pathogenic mutations in the GAN gene.
• It provides crucial genetic information for diagnosing and managing GAN in the Mexican population.
• Understanding these novel mutations contributes to elucidating the molecular pathology of gigaxonin dysfunction in GAN.