Relatedness and genomic inbreeding in a sample of Timor ponies.

This research paper evaluates the genetic relatedness and estimated levels of inbreeding among a sample of Timor ponies in Australia, with the aim of assessing the feasibility of establishing a domestic breeding program. It uses genotyping data to determine that there are distantly related and minimally inbred horses within the sample, suggesting potential for the success of a breeding program, though it acknowledges the benefits of incorporating additional ponies from other sources.

Study Objectives

• The main goal of this research was to understand the genetic relatedness and inbreeding levels in a sample population of Timor ponies (TPs), originally from Timor and now residing in Australia.
• This was prompted by the interest in establishing a domestic breeding program for these TPs in Australia.

Methodology

• The study used hair samples from each horse which were then genotyped using the Illumina 80K Infinium Equine genotyping array.
• These data were subsequently analysed using different statistical software programs including PLINK v1.90b7, KING 2.3.2, and R v4.3.1.

Results

• The results of the research showed that the sampled TPs contained distantly related and minimally inbred horses.
• The length of the Runs of Homozygosity (ROH) segments in their genomes indicated that inbreeding events had only occurred recently in about a third of the horses.

Implications and Recommendations

• The paper suggests its findings, showing minimal inbreeding and genetic diversity, are promising for a domestic TP breeding program in Australia.
• Although the findings are optimistic, due to the low number of TPs known to be in Australia, the study acknowledges the benefits of adding more TPs sourced from either Timor or areas in Australia which may have wild descendants of TPs.