Structure of equine 2′-5’oligoadenylate synthetase (OAS) gene family and FISH mapping of OAS genes to ECA8p15–>p14 and BTA17q24–>q25.

This research studied the structure of a specific gene family in horses (OAS), which plays a significant role in overcoming viral infections, and mapped these genes to specific locations on horse and cattle chromosomes.

Understanding the Research

• The research article talks about a set of genes present in mammals termed 2′-5′ oligoadenylate synthetases (2-5A). These are involved in the body’s defense mechanism against viruses.
• In both humans and mice, there are four variants of this gene: small, medium, large, and ubiquitin-like. The researchers were interested in studying the similar structure in horses, referred here as equine OAS genes.

Methods and Findings

• The scientists used DNA sequences from 15 cDNA and four BAC clones to study the structure of four equine OAS genes. Here, cDNA and BAC clones mean copies of genetic material used for experimental purposes.
• They found that the equine OAS gene family was more similar to the human OAS family than the mouse Oas family.
• The researchers also identified two BAC clones containing OAS genes in cattle.
• Both horse and cattle BAC clones were physically assigned by FISH (Fluorescence In-Situ Hybridization) to specific areas on the chromosomes of horses and cattle. This technique allows scientists to visualise where certain genes are located on the chromosomes.
• For horse chromosomes, the location was ECA8p15–>p14 and for cattle chromosomes, it was BTA17q24–>q25.

Results and Significance

• Comparative mapping data from the study confirmed that there is conservation of synteny between ungulates (like horses and cattle), humans, and rodents. Synteny refers to the physical co-localization of genetic loci on the same chromosome in different species.
• This would mean that the same block of genes, following the same order, is present across these species. This can serve as a fundamental basis for understanding the evolution of species and may aid in investigating the different responses of species to diseases.