Healthy people aged 18 to 50 who have never given blood for the purpose of testing their bone marrow tissue type in Israel are sought on Tuesday to save the lives of one cancer patient in Israel and another in New York. Ezer Mizion, the national bone marrow bank, will hold a countrywide campaign to find a suitable donor for Eli (Ilya) Tobavin, a 33-year-old man with leukemia who made aliya from Moscow in 1992 with his wife, works at Microsoft and is the father of six-year-old Natalie. Compatible bone marrow is also being sought for Alan Cohen, a New York Jew suffering from cancer who is married and has 12-year-old twins. He has been unable to find suitable bone marrow in data banks in the US, and there is also none at the Ezer Mizion bone marrow bank. One can receive more information about blood-sampling stations, and how to donate money to cover the NIS 180 processing cost, by calling 1-800-236-236. The Web site (www.ami.org.il) also provides information. Bone marrow bank director Dr. Bracha Zisser says that even if you are not found to be compatible this time, your tissue type will be stored in the data bank for future use. Removal of bone marrow is a minimal, harmless procedure, but it can save a life. So far, about half of all Israelis are listed in the Ezer Mizion data bank, but many people still go without a potential compatible donor. So far, 565 samples have been matched, and about 120 bone marrow transplants have been performed on the basis of the matching.