By Caitlin Antonios
For most of his career, Department of Natural Sciences Professor of Biology Patrick Ferree has been interested in 鈥渟elfish鈥� genetic elements鈥攐nes that cheat the normal rules of genetics.
There is perhaps none more ruthless than a selfish B chromosome known as Paternal Sex Ratio (PSR), which has been a focus of his research for years. PSR is found in nature in the jewel wasp: a tiny, jet black wasp with translucent wings.
In most biological circumstances, offspring receive two sets of chromosomes, one set contributed by each parent. PSR is an exception鈥攊t only appears in adult males and there鈥檚 always only one copy of it.
That head-scratching curiosity led to a research paper by Ferree and his team, including students from Claremont McKenna, Pomona, Pitzer, and Scripps鈥� own Emma Garman 鈥�26. The paper was recently accepted by PLoS Biology, a highly selective and prestigious journal dedicated to publishing advances across the biological sciences.
鈥淧SR is the harshest known genetic element because it will kill the other chromosomes,鈥� Ferree says. It鈥檚 only possible because a wasp can live with one set of chromosomes, which means an egg with a single chromosome set is destined to become a male. 鈥淭he study looks at why it鈥檚 so good at killing that set of chromosomes and whether it can ever be found in females.鈥�
The process
Garman, a biology and art duel major, joined Ferree鈥檚 lab the summer after her sophomore year after emailing professors about gaining more lab experience.
鈥淚t all happened very quickly and last minute, right before summer break,鈥� Garman says. 鈥淚 was so excited and I had read all about his work and I was fascinated by his project.鈥�
The research took place in The Nucleus, the Department of Natural Sciences鈥� interdisciplinary hub shared by 五月天视频and Pitzer Colleges. Garman spent her first few weeks acclimating to the lab, its equipment, and brainstorming approaches to the research.
鈥淓very week I would have dissections, microscopy work, data to analyze, or I would write on process,鈥� Garman says. 鈥淚 read a lot of scientific papers in the early stages as well.鈥�
Garman played a significant role helping young female wasps with PSR mate with male carriers. The team found the chromosome in freshly fertilized wasps but noticed a change when the wasps grew.
鈥淓mma鈥檚 work established that you never see an adult male with two copies of the B chromosome,鈥� Ferree says. 鈥淗er work suggests that you can鈥檛 have two copies because having two copies is lethal to the wasp at some critical stage of development. Also, it鈥檚 the first chromosome known to be incompatible with meiosis (cell division鈥痠n sexually reproducing organisms), and because males don鈥檛 do meiosis, PSR can be transmitted through adult males.鈥�
Garman also spent hours meticulously dissecting and treating samples, looking at them under the microscope, and collecting a robust data set.
鈥淚t was very gratifying and as much as it was a lot of work, it was so much fun,鈥� Garman says. 鈥淚t was such a joy to work with Patrick; I thought the experience was going to be more about me learning these technical skills and how to be in a lab, but he treated me like an equal and brought me into the scientific brainstorming.鈥�
The joy of discovery
While the broader impact of a discovery like this can never immediately be known, Ferree notes that this chromosome-killing element has cross disciplinary implications.
鈥淚f we are able to understand this mechanism, we can envision ways to utilize it,鈥� he says. 鈥淏ut most importantly, it鈥檚 a joy to discover things.鈥�
Part of what made this research possible is Ferree鈥檚 new lab in The Nucleus, which he moved into from his former lab in the basement of Nucleus East while the research was ongoing.
鈥淚t took a lot for this to come together鈥攑ersistence, students, and the quality of the research,鈥� he says. 鈥淭he building is amazingly helpful to give students the opportunity to engage in meaningful work. 鈥淭his is one of the most meaningful publications I鈥檝e had as a professor here because it was done entirely by students in our department and without collaborators at other big institutions.鈥�
As both Ferree and Garman reflect on the process, the innovation of their research shines through. They both value constant problem solving, the cognizance of where human error can play roles, even positive ones, in research, and the freedom to follow curiosity. The creative element of the scientific process has only further attracted Garman to a future in STEAM (science, technology, engineering, arts, math).
鈥淚 want to pursue this intersection of art and science,鈥� Garman says. 鈥淭hat is one of the biggest ways, aside from developing into the person I am right now, 五月天视频has shaped me. I know what I want in the next phase of my life, and 五月天视频has given me the confidence to pursue that.鈥�