Should Athletes Be Screened for Sickle Cell Trait?

An extensive and high-profile screening program to test college athletes in the United States for the sickle cell anemia gene has evoked some controversy.

Starting this academic year, the [U.S.] National Collegiate Athletic Association (NCAA) plans to screen close to 167,000 college athletes for sickle cell trait. Students participating in athletics at Division I schools will be tested for the gene responsible for sickle cell disease. The program aims to identify carriers of a single sickle-cell gene--not those who carry two such genes, and have sickle-cell disease.

Those who inherit sickle-cell genes from both parents will have sickle-cell anemia, a chronic and painful disease in which red blood cells fail to carry oxygen efficiently to muscles and organs. However, those who carry a single gene have no outward symptoms of the genetic affliction, which mostly affects those of African descent.

Carriers of the sickle-cell gene are more prone than those without the gene to develop a potentially deadly muscle-wasting condition called rhabdomyolisis after intense physical exertion, as well blockages in blood vessels carrying oxygen to the spleen (especially when exercising at high altitudes).

The proposed [U.S.] National Collegiate Athletic Association (NCAA) screening is expected to identify 400 to 500 carriers each year. Eight percent of African-Americans carry at least a single sickle-cell gene (rates among Latinos and white Americans are .08% and .02% respectively).

In a commentary published in the September 9, 2010, New England Journal of Medicine (NEJM), attorney Vence L. Bonham and scientist Lawrence C. Brody of the [U.S.] National Human Genome Research Institute (NHGRI; Bethesda, MD, USA), and Johns Hopkins Children's Center (Baltimore, MD, USA) pediatrician George Dover noted that the NCAA has failed to put in place measures that protect athletes identified as carriers from stigma or discrimination. Nor have they arranged counseling on what their status means (and does not mean), and how they might protect themselves from the risks that come with it. They warned that the sickle cell testing "may also open the door to additional testing."

The commentary adds that because the tests will take place outside of a patient-physician relationship, athletes will lack confidentiality. The authors noted that for students on athletic scholarships, such testing could be viewed as coercive. In addition, they questioned why the program appears limited only to Division I schools. "Are athletes in NCAA Divisions II and III at less risk, and if not, why are they exempt from testing?"

However, the NCAA fact sheet about sickle cell trait testing states that athletes with sickle cell trait should not be excluded from participation as precautions can be put into place. Most U.S. states test at birth, but most athletes with sickle cell trait do not know they have it.

The NCAA recommends that athletics departments confirm the sickle cell trait status in all student-athletes. Knowledge of sickle cell trait status can be a gateway to education and simple precautions that may prevent collapse among athletes with the trait, allowing them to succeed in their sport.

A growing number of tests--medical and genetic--are becoming available to identify persons at particular risk of disease or injury. As employers and league officials embrace those tests to protect themselves and their members, they may look to the NCAA's new initiative.

Related Links:
[U.S.] National Collegiate Athletic Association
[U.S.] National Human Genome Research Institute
Johns Hopkins Children's Center