Marsupial Y chromosome encodes a homologue of the mouse Y-linked candidate spermatogenesis gene Ube1y

The discovery of a functional marsupial Y-linked homologue gene of the murine Ube1y gene proves that the Metatherian (marsupial) and Eutherian (placental) infraclasses of the mammalian subclass Theria evolved from a single ancestor, probably between 120 and 150 million years before present. This Ube1y gene contributes to the development of males among both marsupials and placentals by triggering spermatogenesis. This finding confirms the molecular and genetic link between marsupials and placentals.