Jennifer Graves’ contribution to understanding the evolution, function and organization of the mammalian genome has had a major effect on current thinking in the field. By exploiting the genetic diversity of Australia’s unique mammals she has brilliantly illustrated the importance of a comparative genomics approach in modern biology, revealing valuable insights into mammalian development, reproduction, genetic disease, disease defence mechanisms, and species survival in general.

An early fascination with genetics led her, after undergraduate studies in Adelaide, Australia, to a PhD in molecular biology at the University of California at Berkeley, thanks to a Fulbright award. On returning to Australia, she realized the potential of the rich genetic resource provided by her country’s unique mammals (marsupials, like the kangaroo, and monotremes, like the duck-billed platypus) to study genetic structures which have been conserved from the earliest mammals through to humans.

Based at La Trobe University in Melbourne, where she spent 30 years before moving to the Australian National University in Canberra in 2001, much of Professor Graves’ career has been dedicated to studying the evolutionary history of the X and Y chromosomes. One of the most fascinating discoveries made in her ‘Jennytech Lab’ was completely unexpected and changed the way biologists view sex differentiation in mammals.

In humans and other mammals, females have two copies of the X chromosome while males have only a single X plus a smaller Y chromosome. Her team discovered that a gene on the human Y chromosome thought to be responsible for testis development, and thus for ‘maleness’, was not located on the Y chromosome in marsupials. This discovery led two of her former students to identify the correct sex-determining gene (known as SRY) present on the Y chromosome in both eutherian mammals, such as humans or mice, and in marsupials, which branched off the evolutionary tree some 130 million years ago. Much of her work since then has been dedicated to elucidating the mystery of how this gene has evolved and the complex pathway of gene activation and inhibition which regulates testis formation.

More recently Jennifer Graves’ imaginative approach to research has led her to uncover another fascinating secret held by Australia’s fauna. Using an elegant labelling technique known as chromosome painting, she demonstrated that the duck-billed platypus, one of only three representatives of the monotremes, which diverged from marsupial and eutherian mammals some 210 million years ago, has ten sex chromosomes: five X and five Y. Even more astounding was the discovery that these chromosomes share genes with both bird and mammal sex chromosomes, thus challenging the accepted view that bird and mammal sex chromosomes evolved independently.

Throughout her career, Professor Graves has been an untiring advocate for comparative genomics. As co-chair of the International Comparative Gene Mapping workshops, she ensured that its importance was recognized within the Human Genome Project. In 2004 she became director of the new ARC Centre for Kangaroo Genomics in Melbourne which was set up to secure a key role for Australia in the future sequencing of the kangaroo genome.

By deepening understanding of the past evolution of sex determination, Jennifer Graves has paved the way for developments in diagnosis of gender disorders and gender-related disease in humans. She also hopes it will open up a more fundamental debate about the future evolution of the human species. This creative and inquiring approach has also given Professor Graves an outstanding reputation as an inspiring teacher and mentor.

Her contributions to science have been recognized through numerous awards and honours. She was elected fellow of the Australian Academy of Science in 1999 and awarded a Centenary Medal for services to Australian genetics and genomics in 2002. She also was awarded the L’Oréal-UNESCO Award for Women in Science 2006 as the Laureate for the Asia/Pacific. Jenny is currently a Professor at the Australian National University, Canberra and also acts as a Director of the ARC Centre for Kangaroo Genomics at the University of Melbourne.