Genetic markers correlated with Native American ancestry are associated with a higher risk of relapse among children treated for acute lymphoblastic leukemia (ALL), according to a study published online this week in Nature Genetics.
Ethnic differences in survival among children with ALL have been reported in many clinical studies, with poorer survival observed among African Americans or those with Hispanic ethnicity when compared with European Americans or Asians. However, the underlying causes for this are uncertain. Mary Relling and colleagues analyzed genetic variation in 2,534 children with ALL and found that the component of genetic variation that correlated with Native American ancestry was associated with a higher risk of relapse following chemotherapy, even after adjusting for known prognostic factors. The study also found that ancestry-related differences in relapse risk were eliminated by the addition of a single extra phase of chemotherapy, suggesting that treatment modifications can mitigate ethnic disparities in outcome among children with ALL.