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Updated: May 16, 2026
08:27
Large-Scale Multi-Omics Genome-Wide Association Studies (Mo-GWAS): Guidelines for Sample Preparation and Normalization
Published on: July 27, 2021
Comparative genomics and transcriptomics of trait-gene association.
Sebastián Aguilar Pierlé1, Michael J Dark, Dani Dahmen
1Program in Genomics, Department of Veterinary Microbiology and Pathology, Paul G, Allen School for Global Animal Health, Washington State University, Pullman, WA 99164-7040, USA. saguilar@vetmed.wsu.edu
BMC Genomics
|November 28, 2012
Summary
Researchers identified 30 genes and two novel transcripts potentially involved in tick transmission of Anaplasma marginale, an important cattle pathogen. This study used comparative genomics and RNA-seq to dissect bacterial pathogenesis and transmission.
Area of Science:
- Microbiology
- Genomics
- Pathogenesis
Background:
- The Order Rickettsiales contains significant tick-borne pathogens like Rickettsia rickettsii and Anaplasma marginale.
- Understanding microbial determinants of arthropod vector transmission is crucial but limited.
- Anaplasma marginale offers distinct strains with reproducible transmission phenotypes for studying transmission.
Purpose of the Study:
- To identify microbial genetic factors influencing Anaplasma marginale tick transmissibility.
- To investigate the role of single nucleotide polymorphisms (SNPs) in transmission phenotypes.
- To characterize the transcriptome of Anaplasma marginale in relation to transmission efficiency.
Main Methods:
- Comparative genomics combining DNA/RNA analysis of A. marginale strains with varying transmission phenotypes.
- Identification of single nucleotide polymorphisms (SNPs) and affected genes/promoters.
- RNA-sequencing (RNA-seq) using multiple platforms to analyze differential gene transcription.
Main Results:
- Comparative genomics identified SNPs in 18 genes and nine promoters correlating with transmission.
- RNA-seq revealed differential transcription in 10 additional genes between strains with distinct transmission efficiencies.
- Six unannotated genomic regions were transcriptionally active, with two showing differential transcription.
Conclusions:
- Identified 30 genes and two novel transcripts potentially mediating Anaplasma marginale tick transmission.
- Provided an in-depth description of the obligate intracellular bacterium's transcriptome.
- Demonstrated the utility of massive parallel sequencing in dissecting bacterial pathogenesis traits.
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