Multi-Omic Approach to Identify Phenotypic Modifiers Underlying Cerebral Demyelination in X-Linked
Phillip A Richmond1, Frans van der Kloet2,3, Frederic M Vaz4,5
1Center for Molecular Medicine and Therapeutics, BC Children's Hospital Research Institute, University of British Columbia, Vancouver, BC, Canada.
Frontiers in Cell and Developmental Biology
|July 17, 2020
Summary
This study sought molecular markers for cerebral adrenoleukodystrophy (CALD) in blood samples. Researchers found high inter-individual variation, suggesting CALD results from environmental and genetic factors, not simple biomarkers.
Area of Science:
- Genetics
- Biochemistry
- Neurology
Background:
- X-linked adrenoleukodystrophy (ALD) is a peroxisomal disorder caused by ABCD1 gene mutations, leading to very long-chain fatty acid accumulation.
- ALD presents complex clinical features, with all males developing spinal cord disease, but only 60% developing cerebral ALD (CALD).
- Early CALD detection is crucial for effective hematopoietic stem cell therapy, but current diagnostic protocols are insufficient for prognosis.
Purpose of the Study:
- To identify prognostic molecular markers for cerebral demyelination in ALD from blood samples.
- To develop blood-based assays for early CALD diagnosis and prognosis.
- To investigate the genetic and environmental factors contributing to CALD development.
Main Methods:
- Multi-omic profiling (genome, epigenome, transcriptome, metabolome/lipidome, proteome) of blood samples from six ALD brother pairs discordant for CALD.
- Analysis focused on identifying discordant genomic alleles and differentially abundant molecular features.
- Univariate modeling was used to discriminate between CALD and non-CALD phenotypes.
Main Results:
- No statistically significant candidate molecular markers were identified to predict CALD.
- High inter-individual variation was observed, complicating the identification of simple biomarkers.
- Confirmed the role of immune response and autoimmunity, and suggested a potential role for PFN1 protein overabundance in a subset of CALD cases.
Conclusions:
- Cerebral demyelination in ALD likely results from a complex interplay of environmental factors and heterogeneous genetic alleles.
- Simple molecular markers from blood are insufficient for predicting CALD due to significant inter-individual variability.
- The study provides a valuable dataset and methodology for future research into ALD modifiers and potential therapeutic targets.
