In two conversations, we spoke about his experience growing up with hemophilia, his sense of identity, and his hopes for his newborn baby girl. The interview has been lightly edited and condensed for clarity.

Sarah Zhang: Tell me about your experience living with hemophilia.

Jeff Johnson: As early as I remember, honestly, I was having to go in to the emergency room for regular injections. I was on a different medication at the time, cryoprecipitate [which is derived from blood plasma and contains clotting factors]. I remember some kind of foggy memories as a toddler. The cryo was frozen, so it would have to sit out on the counter and thaw, and then they would do the infusion, and it would drip in over the course of a couple of hours.

There were people who were on clotting factor [which could be stored at home] when I was a kid. The hematologist had told my dad that factor might not be safe. There were hemophiliacs getting sick from it, so my dad didn’t let them use factor on me. It turns out hemophiliacs were getting sick because they were contracting HIV from their factor, so I was on the older treatment, but it ended up saving my life.

Right now, I deal more with the aftereffects of bleeds that I had years ago than I do with bleeds today. I had arthritis in my knees since my early 20s. I have arthritis and damage in my spine from bleeds, so those things just, they kind of wear on you more and more. I did get hepatitis, but I didn’t get HIV.

Zhang: You’ve been talking about some of the challenges of living with hemophilia. So why are you personally not interested in a cure?

Johnson: The analogy I offer people, and I offer to you, is, as a woman, I’m sure you experience difficulties and challenges just being a woman in life. If someone came to you and said, “We’ve got a genetic cure for being a woman,” that would be really bizarre to you because being a woman is who you are.

I am hemophilia. I don’t have it. I am hemophilia. So when they come to me and say, “We’ve got a genetic cure for hemophilia,” to me, that’s just as weird as if you said you’ve got a genetic cure on the horizon for your left foot. This is really who I am. So I don’t necessarily see it as something that needs a cure. As far as genetic cures go, the whole principle of changing my DNA is something I’m not comfortable with. A lot of us that grew up with it, it’s part of our identity, so we don’t really see separating our identity from us.

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Zhang: Not everyone in the hemophilia community feels the same way about gene therapy or gene editing, of course. One thing I’ve heard talking to people with hemophilia is that for older folks—who grew up in the ’70s and ’80s when treatment was not as good and then lived through the HIV epidemic—there is a really strong sense of identity and community. Do you sense a generational divide in attitudes about a cure that would fundamentally alter your DNA?