Invulnerable Leukemias

Leukemias with inherited BAALC gene are difficult to treat

/ Author:  / Reviewed by: Robert Carlson, M.D

(RxWiki News) The genes you inherit from your parents can be sort of a mixed bag. While some traits like height and eye color can be straightforward, some are complex relationships that take a detective to find the full implications.

Scientists recently identified a genetic basis for leukemias that do not respond to therapy, and in the process they discovering that the responsible gene was inherited, rather than a random mutation.

"Ask your doctor about cancer risk factors."

Researchers from Ohio State University identified a gene called BAALC which is involved in the regulation of cellular division. While the mutation is silent in most people, the gene goes into overdrive during episodes of acute leukemia, ignoring several common leukemia treatments, and researchers were at a loss to explain how.

As it turns out, the importance of the BAALC mutation was changing the amount of activation by another protein called RUNX1. The mutation by a single letter of DNA broke the mechanism entirely.

As scientists discovered, the breakdown in the normal interaction of the BAALC protein, which is responsible for cell division, and RUNX1, which is responsible for normal cell development, is the perfect recipe for an unusually hardy leukemia.

Formally called "brain and acute leukemia, cytoplasmic" the BAALC gene was identified in an early genetic survey but the full significance of the gene was not fully explored until now.

Identifying leukemia patients with this gene, BAALC, is important because doctors can focus on what does work for those patients rather than losing valuable time on ineffective therapies.

Initial research was performed in the lab and 253 patients were found with the relationship between BAALC and RUNX1. Further proof was found in a second study using data from an unrelated acute myeloid leukemia study in Germany where the same genetic relationship between the two proteins was identified.

As explained in the paper, just a single change of one letter in the DNA means that the BAALC gene never shuts off, causing the uncontrolled cellular division that becomes leukemia.

Researchers were quick to point out that this gene mutation doesn't mean that people with the gene are more likely to develop cancer, just that several therapies are not effective when this mutation is involved.

"We want to emphasize," states the principal investigator Albert de la Chapelle, MD, "that this SNP [single nucleotide polymorphism] does not raise an individual's risk of developing leukemia, but it does predispose to overexpression of the BAALC gene, which is associated with leukemia development and poor response to treatment."

The study was published in the journal Proceedings of the National Academy of Sciences of the United States of America on April 24, 2012.

Study authors declared no financial conflict of interest with the publication of this research.

Reviewed by: 
Review Date: 
May 30, 2012
Last Updated:
June 5, 2012