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Tackling Heart Disease with Geneticist Tafadzwa Machipisa

For #BlackHistoryMonth, Science World is amplifying scientific and artistic voices in the Black community. Their contributions to STEAM are making history. Celebrate with us!

Growing up in a farming family in Zimbabwe, Tafadzwa Machipisa first explored genetics and biology in cornfields. Today, she is a PhD candidate at McMaster University and the University of Cape Town. Listen to her story about deciphering the genetics of rheumatic heart disease, which has its highest prevalence in Sub-Saharan Africa.

Full audio transcript below

Tafadzwa Machipisa joined the Mayosi research group's cardiovascular genetics team in 2015. Her work entails deciphering the genetics of rheumatic heart disease (RHDGen) using bioinformatics, genetic epidemiology, and statistical genetics methods. She is currently supervised by an international cohort of Professors: B Mayosi, M Engel (South Africa), G Pare (Canada), and B Keavney (UK). During her free time, she leads the African Caribbean Graduate Student Association (ACGSA) and lives in Symbiosis housing.

Celebrate with us.

Every week in February, we're sharing a new audio or visual story amplifying scientific and artistic stories from voices in the Black community for #BlackHistoryMonth.


Tafadzwa Machipisa (TM): When I was younger, and up until this day, I’ve always been fascinated by genetics.

Narration: That’s Tafadzwa Machipisa, a PhD student in computational and statistical genetics.

TM: So I grew up in Africa, in Zimbabwe specifically. In my family, I was the darkest child. And I had siblings who were fairer than me and quite a number of family members who were fairer than me. And also I had other friends whose families were multiracial. So it just always fascinated me on the similarities and the differences.

Narration: Tafadzwa asked her mother, a farmer, about these similarities and differences. Her first lesson in genetics came through the biology of their main crop, corn.

TM: So, she’d show me, “You see, this last season I had bi-color corn, or yellow corn or white corn. If I mix it up like this, or if I mix this type of seed and that one, the yield changes.” For a while, I kept on asking her questions and she said, “Yeah, you know, you could always go into genetics because that’s actually what dictates these changes in the humans you keep on asking me about and in the plants.”

Narration: Tafadzwa took her mother’s advice and followed her passion for genetics all the way to her current dual PhD program. she studies at the University of Cape Town in South Africa in the Department of Medicine. She also studies at McMaster University in the Department of Pathology and Molecular Medicine. Tafadzwa had a number of projects related to genetics that she could choose from, and just like the inspiration from her mother, it was the excitement of a certain supervisor that made her choice an easy one.

TM: The enthusiasm of Professor Bongani Mayosi was actually the thing that made me think, “I want to join that group. I want to have what he’s having! Because he’s so happy and excited about his project.” So, that’s actually how I ended up in heart disease genetics. And why I stayed was, there’s a large burden of heart diseases across the world.

Narration: Rheumatic heart disease affects over 39 million individuals worldwide and causes over 300,000 deaths every year. The highest prevalence of this disease is found across Africa. Particularly in Sub-Saharan Africa. Tafadzwa is passionate about deciphering the genetics of rheumatic heart disease because it’s preventable and because it affects children.

TM: So, at your left side of your heart there’s the upper chamber and the lower chamber and in between those two chambers there’s little valves that control blood coming in and out of your heart and those are actually the little flaps that are destroyed by this auto-immune response. And, once they’re damaged, you have what is called rheumatic heart disease. Basically, you could avoid it by taking penicillin but a lot of people in low and middle income countries don’t have access to penicillin and it happening several times in small children and now they need heart surgery.

Narration: Tafadzwa is active in student groups on campus. For her and her colleagues, Black History Month is a time of celebration.

TM: When I was in Africa, every day was like Black History Month because most history was about Black people like me. in Africa, we’ve always known about people like Harriet Tubman and Sojourner Truth but, when you now live where these individuals lived, you kind of understand what it is to be a minority and why people who are minorities would like to especially hold onto this month because for them they feel like it’s the one time they can share about their own personal history and there’s a lot of things that make them feel more like they fit somewhere.