Navigation Links
Native American ancestry linked to greater risk of relapse in young leukemia patients

The first genome-wide study to demonstrate an inherited genetic basis for racial and ethnic disparities in cancer survival linked Native American ancestry with an increased risk of relapse in young leukemia patients. The work was done by investigators at St. Jude Children's Research Hospital and the Children's Oncology Group (COG).

Along with identifying Native American ancestry as a potential new marker of poor treatment outcome, researchers reported evidence the added risk could be eliminated by administering an extra phase of chemotherapy. The study involved 2,534 children and adolescents battling acute lymphoblastic leukemia (ALL), the most common childhood cancer. The work appears in the February 6 advance online edition of the scientific journal Nature Genetics.

The children were all treated in protocols conducted by St. Jude or COG. Although the overall cure rate for childhood ALL now tops 80 percent, and is close to 90 percent at St. Jude, racial and ethnic disparities have persisted. Based on self-declared status, African-American and Hispanic children with the disease have often fared worse than their white and Asian counterparts. This is the first study to use genomics to define ancestry, rather than relying on self-declared racial or ethnic categories.

"To overcome racial disparity you have to understand the reasons behind it," said Jun Yang, Ph.D., St. Jude Department of Pharmaceutical Sciences assistant member and the study's first author. "While genetic ancestry may not completely explain the racial differences in relapse risk or response to treatment, this study clearly shows for the first time that it is a very important contributing factor."

This study identified a possible mechanism linking ancestry and relapse. Hispanic patients, who have a high percentage of Native American ancestry, were more likely than other patients to carry a version of the PDE4B gene that was also strongly associated with relapse. The PDE4B variants were also linked with reduced sensitivity to glucocorticoids, medications that play a key role in ALL treatment. "This is just one example of how ancestry could affect relapse risk," said the study's senior author Mary Relling, Pharm.D., St. Jude Pharmaceutical Sciences chair. "It is likely that many other genes are involved."

Investigators also found ALL patients with greater Native American ancestry who received additional chemotherapy as part of a COG clinical trial benefited more from the extra treatment than other children. "These are important steps on the way to personalized cancer care, whereby treatment can be tailored to provide maximal benefit to patient subgroups, and someday, individual patients," said co-author Stephen Hunger, M.D., University of Colorado professor of pediatrics and chair of COG's ALL committee.

For this study, scientists used a library of 444,044 common genetic variations known as single nucleotide polymorphisms, or SNPs, to search each patient's DNA for evidence linking ancestry and relapse. The study found that cancer was 59 percent more likely to return in patients whose genetic makeup reflected at least 10 percent Native American ancestry.

About 25 percent of patients in this study met the 10 percent threshold. The percentage was highest among the self-reported Hispanic and Native American patients, who have been reported to be at higher risk of relapse.

Native American ancestry identified patients at high risk of relapse missed by current clinical tools, including testing for minimal residual disease (MRD), which measures the cancer cells that survive the initial round of therapy. Relling said additional research is needed to confirm the findings before screening becomes part of clinical care.

This study used advances in high throughput genomic technologies to better understand why cancer treatment sometimes fails and how the failure is related to genetic ancestry. Unlike previous research that relied on patient self-reports of race and ethnicity and focused on specific populations, this study focused on a group of patients as diverse as the U.S. and representative of the nation's entire ALL population.


Contact: Summer Freeman
St. Jude Children's Research Hospital

Related biology news :

1. Neiker-Tecnalia creates air-conditioned greenhouse with alternative energies
2. Home and away: How do invasive plant species dominate native species?
3. ONR, Marine Corps show alternative energy use at forward operating bases can save dollars, lives
4. The world can be powered by alternative energy, using todays technology, in 20-40 years
5. Virginia Tech engineers introduce thermotherapy as a chemotherapy alternative
6. Electricity collected from the air could become the newest alternative energy source
7. College students want more information about native wildflowers
8. Potomac River: 10-fold increase in native submerged vegetation reflects improved water quality
9. Is organic farming good for wildlife? It depends on the alternative
10. Trojan Horse attack on native lupine
11. Native-like spider silk produced in metabolically engineered bacterium
Post Your Comments:
(Date:11/4/2015)... ALBANY, New York , November 4, 2015 /PRNewswire/ ... According to a new market report published by Transparency ... Size, Share, Growth, Trends and Forecast 2015 - 2022", ... value of US$ 30.3 bn by 2022. The market ... during the forecast period from 2015 to 2022. Rising ...
(Date:10/29/2015)... Daon, a global leader in mobile biometric ... new version of its IdentityX Platform , IdentityX ... have already installed IdentityX v4.0 and are ... FIDO UAF certified server component as an option ... features. These customers include some of the largest and ...
(Date:10/29/2015)... , Oct. 29, 2015 Today, ... a partnership with 2XU, a global leader in ... a smart hat with advanced bio-sensing technology. The ... athletes to monitor key biometrics to improve overall ... partnership, the two companies will bring together the most ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... ... 2015 , ... Copper is an essential micronutrient that all ... copper is also toxic to cells. With a $1.3 million award from the ... a systematic study of copper in the bacteria Pseudomonas aeruginosa (P. aeruginosa), a ...
(Date:11/24/2015)... -- Clintrax Global, Inc., a worldwide provider of clinical research services headquartered ... the company has set a new quarterly earnings record in Q3 ... posted for Q3 of 2014 to Q3 of 2015.   ... , with the establishment of an Asia-Pacific ... United Kingdom and Mexico , with ...
(Date:11/24/2015)... ... November 24, 2015 , ... The Academy of Model ... Group (SIG), MultiGP, also known as Multirotor Grand Prix, to represent the First–Person View ... years. Many AMA members have embraced this type of racing and several new model ...
(Date:11/24/2015)... -- Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced that its Annual General Meeting ... Israel time, at the law offices of ... th Floor, Tel Aviv, Israel . ... Izhak Tamir to the Board of Directors; , election of ... approval of an amendment to certain terms of options granted to our ...
Breaking Biology Technology: