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Ask Len Your Questions

ByTom MillerThe Secret Life of Scientists and EngineersThe Secret Life of Scientists and Engineers


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ick here for Len’s Profile.

Shofar-playing zebrafish can ask as many questions as they’d like!

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And Len promised to give you some really fine answers.

Q: Ms. Naymark’s Class

Dr. Zon,

Thank you so much for sharing what you do. My students enjoyed learning about your zebra fish lab. They had some questions for you:

1) Can you make a multi-colored zebra fish?

2) Do you put cancer genes in the fish, or do they already have them?
3) Do you ever feel bad putting diseases in the fish?
4) What is your favorite song to play on the trumpet?
5) What made you want to be a biologist?
6) Do you and your brother ever play music together?
7) What is the weirdest thing that has ever happened in the lab?
8) Have you ever been to the Mayo Clinic? We live in Rochester, MN and know that Mayo also has a zebra fish lab.
9) We have a student who is working on a science fair project with Zebra fish, do you have any advice for her?

Thanks for answering our questions!

A: Len Zon

1. Yes. We have some fish that are red in some tissues, green in other tissues, and also have blue muscle.
2. Fish do develop cancer. We have put human cancer genes into the fish, and the fish develop tumors.
3. The lab treats the fish with respect, and we only do our experiments with the goal of helping humans with disease.
4. I like to play the Haydn Trumpet Concerto. But also a song called I remember Clifford.
5. I have always enjoyed chemistry and biology. My two uncles were doctors, and so they got me interested.
6. Yes. We had a band in high school. The drummer in the band is now the prinicipal percussionist in the Pittsburgh symphony.
7. once a technician was monitoring for radioactivity, and the entire lab was blazing. We thought that someone must have spilled a vial with radioisotopes because the Geiger counter was very loud. Then we found out that the technician had had a bone scan that day, and it was just him and not the lab that was radioactive.
8. Never been there. My friend Steve Ekker has a wonderful lab there.
9. Always show how the fish resembles humans. Our story on ferroportin, published in Nature, 2000 is a good story for relevance. It was the first time the zebrafish was used to find a new human disease.

Q: Sherry Austin

Len, you’re a hematologist. I have Selective Immunoglobulin M Deficiency. It is evidently primary. I went to a hematologist/oncologist to make sure it was primary and he said, “I’ve never seen it.” He looked at me like an alien! What do you know about it?

Also, where do you get all the sea monkeys you feed our zebra fish???

A: Len Zon

You should see an allergist/immunologist. They are experts in IgM deficiency.

We get the sea monkeys from Utah.

Q: Miss Johnson’s Class

Hi Len! Thanks for sharing your science and secret. My class has a few questions for you:

1) What is your favorite zebrafish color?
2) When did you become interested in biology?
3) Do you have any people that inspired you to do cancer research?
4) What was your pet frog’s name?
5) Some people have said that chocolate can help to cure cancer. Have you ever given the zebrafish chocolate?
6) Why do fish have the same genetics as humans?
7) How far away do you think you are from finding a cure for cancer?


A: Len Zon

1. I like the green. It is very bright.
2. It was in college. I always liked chemistry, but in college I was exposed to some very good teachers and that stimulated me to do research in biology.
3. My mother died of breast cancer, so that is a motivation. My mentor in medical school was a hematologist/oncologist.
4. We actually named our two frogs after our two kids, Becky and Tyler.
5. Never give zebrafish chocolate. I doubt that it can cure cancer, but I like how chocolate tastes.
6. Most vertebrates have the same set of genes, and also they are diploid. That means that they have chromosome pairs.
7. We have a paper that is about to be submitted with a new potential therapy for melanoma. I’d like to think that we are 5-10 years away.


Original funding for "The Secret Life of Scientists and Engineers" was provided by the Alfred P. Sloan Foundation.