UNIVERSITY PARK, Pa. — Penn State alumnus Mitchell Weiss, chairman of the Department of Hematology at St. Jude Children’s Research Hospital, is one of three Eberly College of Science alumni to have received the 2024 Outstanding Science Alumni Award. The award recognizes and rewards outstanding Penn State science alumni for their success as leaders in science and for the impact they have had on society and their professions.
Weiss graduated from the Eberly College of Science in 1980 with a degree in biophysics. For 15 years he served on the faculty of the University Pennsylvania School of Medicine and Children’s Hospital of Philadelphia. In 2014, he moved to be the chairman of the Hematology Department at St. Jude Children’s Research Hospital, where he studies the biology of blood development and adapting genome engineering tools to treat genetic blood disorders.
In his research, Weiss leads a team of scientists and physicians to find treatments for sickle cell disease using CRISPR-Cas9. Throughout his career, Weiss has mentored over 40 trainees, most of whom have progressed to higher learning and productive careers in academia or industry. Weiss’s mission as hematology chairman at St. Jude Children’s Research Hospital is to facilitate cutting-edge basic, translational and clinical research; foster faculty and trainee development; and promote outstanding clinical care for patients with classical hematology disorders.
In this Q&A, Weiss chatted with the Eberly College strategic communications office about his time at Penn State and his impactful career as a physician-scientist.
What is one of your favorite memories from your time at Penn State?
Weiss: When I was an undergraduate student in the Department of Biophysics, there were about five or six professors who really loved science and who loved learning. I remember a course in the biophysics department where we discovered tissue ultrastructure using electron microscopy. At the time it was a graduate course, so I asked the Director, Dr. Harald Schraer, if I could join the course. He agreed to let me in as long as I worked hard and did well.
In this course, we examined rat tissues using electron microscopy. I was able to schedule time alone on this giant, expensive electron microscope, where I explored the ultrastructure of the tissues. I took pictures, and I didn’t know what I was looking at, so I went home and looked it up. It was so exciting because it was my first exposure to scientific discovery. What I remember most from my time at Penn State 40 years ago is that my professors taught me to love science. That experience set me on my course because it showed me science could be exciting.
How did your time at Penn State shape you as a scientist?
Weiss: My mentors at Penn State taught me to love science. I can’t remember very much about the science that we learned, but I remember the passion. Everyone who I can remember working with promoted that. So, when I left Penn State, I had a love for science which influenced me greatly. I remember the career decisions that I made after Penn State as a series of somewhat random choices. But I was prepared to recognize good opportunities and I took them as they arose. My time at Penn State gave me a great background to go to medical school and to do research.
Can you tell us about what you’re doing now at the St. Jude Children’s Research Hospital, and what’s the most rewarding thing about your work?
Weiss: Currently, I am the chairman of the hematology department, where we study blood and blood diseases. The department has two halves: a clinical side, where we treat patients with a variety of classical blood diseases like sickle cell anemia, aplastic anemia, and bleeding disorders; and a laboratory research side, where study basic science as a route to develop new therapies. We are located in Memphis; Tennessee and our Hematology Department physicians take care of children who live in the surrounding areas. We see patients with sickle cell disease, aplastic anemia, hemophilia, and other bleeding disorders. The experimental research side of my department tries to make discoveries to help patients with those diseases.
One of the things I love about working at St. Jude is that we don’t charge patients anything, so the amount of money one has doesn’t affect the care at all. This provides dignity to patients and families who are poor. It feels good to be able to offer free care to those patients.
Another satisfying part of my job is the research we do. I’m mostly a researcher, and we have a lot of resources thanks to generous donors who fund our research. St. Jude will supplement our research grant funding in ways that allow us to do things we couldn’t do anywhere else. Right now, we’re developing new gene therapies for sickle cell disease and hemophilia using CRISPR-Cas9.
I also enjoy being the chairman because a large part of my job is helping junior trainees and faculty become successful. By doing that, I can have more impact than just with my work.
You clearly have a passion for mentoring trainees. Do you have any advice for being a good mentor?
Weiss: Listen, always put the other person before yourself, and don’t have selfish reasons to help someone. Help people for the sake of helping and be proud of the people that you can help.
The scientific community has a short-term memory. After retiring, very few scientists are remembered for the science they did. But people remember people. The people who you help and the scientific community that you serve will remember you.
How can students select good mentors?
Weiss: It is unusual to have one person meet all your mentorship needs. Often, you will need to seek out specific individuals to help with specific problems or issues. The way to do that is to be curious and to show interest in other people who represent potential mentors. Try to get to know people whom you admire, and ease into the situation. The best mentors that I’ve had have been very hands-off and non-directive. These people mentored me by example, versus telling me what to do. Sometimes you’ll even realize someone is your mentor only after interacting with them for a long time.
How has mentorship influenced your work as a scientist?
Weiss: Ross Hardison, who nominated me for the Outstanding Science Alumni Award, mentored me by example. When we met, Ross worked in the basement of Althouse Laboratory, where he studied red blood cell development and gene expression. Ross was one of the most generous and helpful scientists. When he identified results, he immediately posted them for public use rather than keeping the findings to himself. He helped me with my bioinformatics work and showed me how to behave by example. Ross exemplified that being a good scientific citizen is better in the long run than being secretive and overly competitive.