PEX1 mutations in the Zellweger spectrum of the peroxisome biogenesis disorders

Area of Science:

• Genetics
• Molecular Biology
• Biochemistry

Background:

• Zellweger spectrum disorders are a subgroup of peroxisome biogenesis disorders (PBDs).
• These autosomal-recessive diseases cause widespread pathology, including neurodegeneration.
• The spectrum ranges from severe Zellweger syndrome (ZS) to milder forms like neonatal adrenoleukodystrophy (NALD) and infantile Refsum disease (IRD).

Purpose of the Study:

• To provide an overview of known PEX1 gene mutations.
• To analyze genotype-phenotype correlations in Zellweger spectrum disorders.
• To offer revised mutation nomenclature and updated correlations for clinical utility.

Main Methods:

• Review of identified PEX1 mutations, including insertions, deletions, nonsense, missense, and splice site mutations.
• Analysis of mutation types (e.g., premature truncation codons - PTCs) and their distribution within the PEX1 gene.
• Correlation of mutation impact and location (e.g., AAA domains) with clinical phenotypes.

Main Results:

• PEX1 mutations are the most common cause of Zellweger spectrum diseases.
• PTC mutations are distributed throughout the gene, while missense mutations often cluster in AAA domains.
• A broad correlation exists between mutation type/impact and disease severity (PTCs with severe ZS, missense with milder phenotypes), though exceptions occur.

Conclusions:

• PEX1 mutations significantly influence the clinical presentation of Zellweger spectrum disorders.
• Understanding specific PEX1 mutations and their genotype-phenotype correlations is crucial for accurate diagnosis and management.
• Revised nomenclature and updated correlations enhance the clinical diagnostic utility for these PBDs.