Racial Disparities in Genetic Detection Rates for Inherited Retinal Diseases

ImportanceThe association of race and detection of pathogenic variants using wide-panel genetic testing for inherited retinal diseases (IRD), to our knowledge, has not been studied previously.ObjectiveTo investigate the genetic detection rates of wide-panel testing in Black and non-Hispanic White patients with IRDs.Design, Setting, ParticipantsThis 2-group comparison used retrospective patient data that were collected at the University of Michigan (UM) and Blueprint Genetics (BG). At UM, inclusion criteria included having a clinical IRD diagnosis, wide-panel genetic testing, and both parents and the patient self-identifying as the same race (Black or non-Hispanic White). Logistic regression analysis was used; the dependent variable was genetic test result (positive or negative/inconclusive) and the independent variables were race, age, sex, phenotype, and number of genes tested. In the BG database, patients with wide-panel testing and self-reported race were included; detection rate comparison analysis based on race was performed using χ2 test of independence. These data were analyzed from October 30, 2013, through October 26, 2022.Main Outcome and MeasureGenetic test result was considered positive if pathogenic/likely pathogenic variants were detected.ResultsA total of 572 patients were included in UM, 295 were males (51.6%). Mean age was 45 years. There were 54 Black patients (9.4%) and 518 White patients (90.6%). Black race (odds ratio [OR], 0.25; 95% CI, 0.14-0.46; P < .001) and age (OR per 10 years, 0.84; 95% CI, 0.76-0.92; P < .001) were independently associated with decreased odds of a positive test. In the BG database, 142 of 320 of Black patients (44.4%) had a positive/likely positive test result, a proportion lower than White patients (1691 of 2931 [57.7%]) (χ2 = 18.65; df = 1; P < .001).Conclusions and RelevanceResults from this study highlight a lower genetic detection rate for Black patients than for White patients with IRDs. This supports a concern that the current development of IRD therapeutics is highly dependent on the ability to identify the genetic cause of disease. Patients with no known genetic diagnosis may be disadvantaged in terms of prognostication, inheritance counseling, reproductive decision-making, and eligibility for potential therapeutic options, including clinical trials. As future treatments become available, these findings suggest the need to examine the genetic detection rates across majority and minority subgroups alike.