Researchers from University of Toronto (U of T) have developed a new way to study the early stages of degeneration of Y-chromosome. They have done so by assessing the process in plants.

A number of species are there whose sex gets determined on the basis of which chromosome (X or Y) they have adopted. To cite an example, in humans, if individuals inherit X chromosome of their father then they become females (XX). If individual inherits their father's Y chromosome then they become male (XY).

Sex determination process is said to have evolved independently a number of times. During this process, Y chromosomes have degenerated genetically and a number of genes have lost over time. For now, the process that takes place during the earliest stages of the evolution could not be understood.

As per Prof. Spencer Barrett, the Y chromosome in humans has undergone massive gene loss and now has around 3% of its ancestral genes. Not much is known about the process as it has happened long before.

The Y chromosomes in humans and other animal species started degeneration hundreds of millions of years ago. But such is not the case with plants. Having separate sexes in plants is quite a new phenomenon making them ideal for the study.

Just about 6% of flowering plants are males and females and rest of them are hermaphrodites, said professor Spencer Barrett from U of T. Researchers tested Y-chromosome degeneration in Rumex hastatulus.

They noticed that despite their recent origin, the genes on the Y chromosomes have started degeneration. "The sex chromosomes in Rumex hastatulus are particularly interesting because of the recent emergence of a new sex chromosome system, in which some males carry a second, even younger, Y chromosome", affirmed Prof. Josh Hough.