*Note to readers: Enjoy this previous article by Dr. Jack Brown, who was unavailable this week.
The DNA code is the record keeper of the past, present and a wonderful predictor of the future. You can think of DNA as a grand book that has recorded the living history of the Earth.
The chapters of this book are the genes of DNA. Each gene tells a story, explaining some aspect of an organism’s characteristics. There are genes that organize development and control body plans, genes that make defensive molecules and venoms and genes that run your metabolic functions. The stories they tell are numerous and diverse.
If you want to learn more about the story of an individual gene, the National Institutes of Health provides a wonderful reference page as part of its U.S. National Library of Medicine. There is an absolute wealth of information contained within the library. They have a variety of resources for researchers, publishers, educators, librarians, health care professionals and the general public. It is a science nerd’s paradise, and I encourage you to explore www.nlm.nih.gov when you get a chance.
The page I will focus on in this article is home to the stories of our genes. It is called the Genetics Home Reference, and it is a valuable public resource that covers a genes functions, chromosome location, diseases related to the gene and a variety of other resources related to the gene.
This story is about the gene known as Pax 6.
Humans have 23 pairs of chromosomes, and this gene can be found on chromosome 11 in our species. It is a gene that can be found in a great many species, and it is involved in the development of the eye. Mutations in this gene are associated with a variety of eye disorders in humans.
Pax 6 gained fame in scientific circles when it was implicated as the gene that controlled the development of eyes in fruit flies. That may not sound like much, but a brilliant pioneer in molecular developmental biology name Dr. Walter Gehring, University of Basel, discovered that this gene also did the same thing in mice and humans, as well as all other organisms with eyes. He had found the master switch gene for making an eye. His research even switched the genes from mice into fruit flies and the gene worked just fine at developing the fruit fly eye. The master switch was the same.
He also inserted the gene in places it did not belong, such as the leg, abdomen and wings of a fruit fly, and it grew an eye in those spots. This shocked the world in 1994, a single gene could control the development of something as complex as an eye. Today the study of the master switch genes that control development is in full swing in a new field known as evolutionary developmental biology (Evo/Devo).
Dr. Gehring passed away in 2014, you can read more about his life and research in an article by Markus Affolter and Kurt Wüthrich titled “Walter Jakob Gehring: A master of developmental biology” at https://www.pnas.org/content/111/35/12574#ref-8.