Hispanic and Asian Children at Higher Rate for Leukemia Treatment Resistance

Hispanic and Asian children are more likely to possess genetic variations that make some patients intolerant to the treatment for Acute lymphoblastic leukemia.

ALL is a type of cancer that affects blood and bone marrow. It is the most commonly diagnosed cancer among children. Most children respond well to treatment, and many are able to make a full recovery.

According to Voxxi, new research publishd by St. Jude Children's Research Hospital in Memphis, Tennessee, reveals genetic variants may make some ALL patients intolerant to the medications used in treatment

The data reveals Hispanic and Asian children have these genetic variations. The NUDT15 gene variant is a contributing factor to the mercaptopurine treatment intolerance.

"We confirmed that variants in TPMT were the strongest predictor of mercaptopurine tolerance but importantly described NUDT15 as another critical locus associated with susceptibility to mercaptopurine intolerance resulting from excessive toxicity," said Jun J. Yang, PhD, of St. Jude Children's Research Hospital in a press release regarding the study.

The variant was found in 9.8 percent of patients with East Asian ancestry and 3.9 percent of patients with Hispanic ancestry. There is much lower occurrence in patients of African or European heritage. Hispanic children are genetically at a higher risk for ALL compared to non-Hispanic white children.

In order to proceed with customary ALL treatment, the patients with the NUDT15 variant must have the doses decreased. It must be decreased as much as 50 percent before treatment can be administered, thereby impacting ALL therapy and preventing recovery.

In addition to ancestry, other genetic variants contribute to ALL medication intolerance such as TPMT gene variants.

Researchers add that more studies need to be done in order to make a full connection between ancestry and mercaptopurine intolerance and to establish a working treatment process for these patients.

"We do not know yet what the exact actions should be for patients who carry the NUDT15 risk variant. This is the subject of our ongoing research," Yang said.

Yang and fellow colleagues conducted genome-wide association studies in 657 children who were enrolled in the Children's Oncology Group AALL03N1 trial.