Scientists at St. Jude Children's Research Hospital have identified inherited variations in two genes that account for 37 percent of childhood acute lymphoblastic leukemia (ALL), including a gene that may help predict drug response.
The findings stem from the first complete search of the human genetic blueprint or genome to look for inherited risk factors for ALL, the most common childhood cancer. Published in the August 16 advance online issue of Nature Genetics, the work offers the first proof based on a complete survey of the human genome that inheritance plays a role in childhood ALL.
Mary Relling, Pharm.D., St. Jude Pharmaceutical Sciences chair and the paper's senior author, estimated that individuals who inherited variations in genes known as ARID5B or IKZF1 are almost twice as likely to develop ALL as those without the variations. Even then, she said, the risk remains low. ALL strikes roughly one in every 75,000 Americans. Sixty percent are children and teenagers.
"The genetic variations alone are not enough to cause the cancer. Like all cancers, pediatric ALL is a multi-factor disease," Relling explained. "But these findings may give us a handle on the mechanism of the disease and drug responsiveness to it."
Exactly the same genes, ARID5B and IKZF1, were confirmed to be altered in British children with ALL. That study was published by the Institute of Cancer Research in Surrey, England, in the same issue of Nature Genetics.
In the St. Jude study, researchers collaborated with colleagues from the Children's Oncology Group (COG), who provided additional cases for genetic analysis. COG is an international group of medical institutions that cooperate in research studies and clinical trials of childhood cancer treatment.
Researchers scanned the genomes of 441 children with ALL and a control group of 17,958 cancer-free individuals for more than 300,000 common genetic variations known as si
|Contact: Carrie Strehlau|
St. Jude Children's Research Hospital