Contact: Alexander Shtifman
Phone: 617-713-8989
alex...@childrens.harvard.edu

IDI Senior Investigator Fred Alt, Ph.D., and research fellow Ali Zarrin, Ph.D., have reported in Science Express that a general mechanism for repairing broken chromosomes plays a key role in enabling immune B cells to produce a vast diversity of antibodies against a multitude of pathogens. This discovery also promises to open up new avenues of investigation into the complex development of lymphomas, cancers that result from abherrent B cell development and faulty genetic repair.

Every year 67,000 Americans are diagnosed with Hodgkin or non-Hodgkin lymphomas, cancers which take hold in lymph tissue and spread throughout the body.

Alt and colleagues reported their results on December 14 in Science Express, an online site previewing articles that will appear in Science magazine. Zarrin was first author on the paper, entitled "Antibody Class Switching Mediated by Yeast Endonuclease Generated DNA Breaks." According to Zarrin, this research helps to explain how broken DNA ends might become joined to each other during the normal process that allows production of different types of antibodies, knowledge which has implications for the mechanism of certain types of genetic translocation that occur in lymphomas of antibody producing cells.

An article commenting on the paper, by Jayanta Chaudhuri and Maria Jasin, also appears in Science Express. Chaudhuri and Jasin, researchers at the Memorial Sloan-Kettering Cancer Center in New York City, praise this new research from the Alt lab for opening up fascinating new questions regarding the process of "class switch recombination" (CSR) which powers antibody diversification, especially in relation to the roles of the AID enzyme and chromosomal switch regions in CSR.

Fred Alt, the scientific director at IDI, is also an investigator at the Howard Hughes Medical Institute. A full explanation of this groundbreaking paper can be found at http://www.hhmi.org/news/alt20061214.html.