There are more African-American kidney disease dialysis patients than white patients, and fewer blacks receive live donor kidney transplants compared with whites. But when these black patients do get a live kidney donation, it’s more likely to come from a relative, according to a new study published in the journal Clinical Transplantation and reported in a Wake Forest Baptist Medical Center press release.

For the study, researchers from the Wake Forest center in Winston-Salem, North Carolina, examined the medical records of all successful kidney donors at the center between 1991 and 2009. The study sample consisted of 73 black and 324 white living kidney donors. (For each case, scientists characterized the relationship between live kidney donors and recipients as strangers, family or friends.)

Findings showed that black donors were more likely to give a kidney to a family member—both blood relatives and in-laws. The study also found that African-American donors were younger than their white counterparts and that they were more likely to give their kidney to a parent. (White donors were more likely to be unrelated to kidney recipients and also more likely to donate to a child.)

“The more we can understand what contributes to people’s willingness to donate one of their kidneys, the better job we can do of educating potential living donors about the need [for donation] and allay fears about the risks,” explained Amber Reeves-Daniel, DO, medical director of Wake Forest Baptist’s Living Kidney Donor Program.

Researchers hope this understanding would improve strategies to recruit both black and white living kidney donors—and that it might get more African Americans to donate a kidney to people who are not relatives.

Click here to read more about the symptoms and risk factors for kidney disease.