No Evidence for Distinct Transcriptomic Subgroups of Devil Facial Tumor Disease (DFTD)

Area of Science:

• Wildlife pathology
• Cancer biology
• Genomics and transcriptomics

Background:

• Contagious cancers, like Devil Facial Tumor Disease (DFTD), are poorly understood wildlife infections.
• DFTD has caused an 80% population decline in Tasmanian devils since 1996.
• Current research focuses on vaccine development due to a lack of treatments.

Purpose of the Study:

• To investigate if different genetic variants of DFT1 exhibit distinct gene expression profiles.
• To determine if transcriptomic differences necessitate varied vaccine components for DFT1 strains.
• To assess the feasibility of a universal vaccine or treatment for DFT1.

Main Methods:

• Applied hierarchical and k-means unsupervised clustering to 35 DFT1 transcriptomes.
• Selected transcriptomes from DFT1's four major phylogenetic clades.
• Utilized validation metrics including Gap statistic, Elbow, and Silhouette methods.

Main Results:

• Unsupervised clustering algorithms yielded conflicting results with low individual method support.
• Validation metrics were ambiguous, contradictory, or suggested a single data cluster.
• Analysis revealed similar gene expression profiles across different DFT1 phylogenetic clades, irrespective of tumor purity.

Conclusions:

• The study indicates that DFT1 variants possess largely similar gene expression profiles.
• A single vaccine or therapeutic strategy may be effective against a broad range of DFT1 tumors.
• Findings offer valuable insights into contagious cancers and inform therapeutic development for DFTD.