Leading pediatric leukemia expert on unique challenges of blood cancer in kids with Down syndrome. Children with Down syndrome have leukemia 20 to 150 times more often than kids without Down syndrome. How understanding of leukemia in Down syndrome can help in treatment of all child leukemia? One of your research interests is leukemia that happens in children with Down syndrome. Dr. Anton Titov, MD. How to treat leukemia in children with Down syndrome? Dr. Shai Izraeli, MD. You know as physicians we sometimes tell it to the other physicians that we should be very open minded. We should look at the "experiment of nature" or "experiment of God”. It depends on your values and beliefs. We should see what we can learn from them. Dr. Anton Titov, MD. Down Syndrome is the most common genetic abnormality. It’s not inherited. It's caused by extra chromosome 21, usually in the egg [oocyte]. But it's the most common genetic disorder. Dr. Shai Izraeli, MD. I must tell you this personal story. In 2000 I returned from the National Cancer Institute, where I studied also a topic that is related to leukemia. I thought. OK, but now I need to look for some interesting problem that I want to study. This medical problem will be independent from what we did before. Then I saw a child with Down syndrome and leukemia. I must say, I didn't sleep all night. Because I thought, OK, that's an interesting problem to study. Dr. Anton Titov, MD. Why is it an interesting problem to study? Because children with Down syndrome have a very high rate of leukemia. They have two types of leukemia. There is a type of leukemia that is called myeloid leukemia. And there is a leukemia type that is called lymphoid leukemia. Children with Down syndrome have 150 times more myeloid leukemia and about 20 times more of lymphoid leukemia. About 3% of all children with Down syndrome have leukemia. This is compared with leukemia rate of 1 in 2000 children without Down syndrome. This in itself is an interesting problem. But this makes it even more interesting. It made it for me a more interesting problem to study. Dr. Shai Izraeli, MD. Children with Down syndrome have an extra arm of chromosome 21 in every cell of the body. But you look carefully at the chromosomes of leukemias in children without Down syndrome. You also study adults with leukemia. You will find that the most common chromosomal abnormality is also an additional copy of chromosome 21. like a child with leukemia, an adult with leukemia may have three copies or four copies of chromosome 21 in their leukemia cells. But not in the body. I thought that we must understand the leukemia in Down syndrome. Then we may help more children with Down syndrome who have leukemia. But it may be also relevant for the general population with leukemia. That actually started the research that I've been doing for 16 years already. Dr. Shai Izraeli, MD. Many cancer research groups in the world have joined. I believe we made really important discoveries. We made both fundamental discoveries how the leukemia develops, what happens in leukemia, what are the processes in leukemia. But also we made the leukemia diagnosis and treatment discoveries that are important for the general population. They are therapeutically important. This has been very exciting leukemia research. The genetics of the leukemia in children with Down syndrome. Dr. Anton Titov, MD. Do they relate to particular presence of certain genes and amplified copies on chromosome 21? Or is it some other genetic influences? Well, that's really interesting! Because with age, I realize that the older you grow, the less you understand. Dr. Shai Izraeli, MD. Every day I learn more about how much I don't understand. it's fascinating! Because we found many genes that have importance in the leukemias of Down syndrome. But we still actually do not understand precisely what on chromosome 21 influences leukemia development. When I say "we", I don't mean only our group, my research group. But I mean the global leukemia treatment community.