Adam Session, Binghamton University – Deciphering Polypoid Genome Ancestry

On Binghamton University Week: Untangling the evolution of hybrid plants can be tricky.

Adam Session, assistant professor of biological sciences, looks into some.

Dr. Session is currently an assistant professor at the Binghamton University Harpur School of Arts and Sciences

His research focuses on genome evolution with a focus on polyploidy and transposable elements.

Deciphering Polypoid Genome Ancestry

If you are interested in science or have kept a garden, you’re probably familiar with hybrids.

Hybrids – common in plants and animals – contain chromosomes from two or more parent species. In some instances, including cotton and goldfish, these disparate parental chromosomes become doubled, a condition known as allopolyploidy.

Unlike past methods of deciphering allopolyploid ancestry, which used comparison with related non-hybrid species, our method allows us to discover distinct ancestries by looking at genomic patterns in the hybrid itself. This will enable us to trace these genomes back to the parent species.

Different species carry different sets of repetitive elements; therefore, if we find different repetitive elements in different chromosomes of a polyploid, we can identify the unique contributions of each ancestor. We applied this method to well-studied polyploids where all ancestors survive, like cotton and tobacco, as well as other species where one or more ancestors may be extinct, like strawberries and goldfish.

In many cases, the ancestors of living polyploids are not known. Using our method, we can deduce the ancestral origin of different chromosomes by studying the polyploid genome itself and dividing the chromosomes into sets, or ‘sub-genomes,’ derived from their various ancestors. In addition to identifying the subgenomes, we can also reveal the order in which they were arranged.

Polyploid genome evolution is not only important to understanding the biology of crops. The ancestor of all vertebrates was also polyploid, so understanding the complex evolution of these organisms informs our own biology as well as those of important agricultural and biofuel systems.

Read More:
[Binghamton] – The ingredients for a strawberry: New method traces ancestry of hybrids