5617 Background: To compare uterine cancer patient characteristics and genetic mutational profiles by age and self-identified ancestry. Methods: Data on uterine cancer patients who had germline, MyChoice, and/or Precise testing were collected from the Myriad Collaborative Research Registry. Mutations in genes of interest were obtained from TAPUR studies currently under enrollment. Graph Pad Prism v 10.1.1 was utilized for statistical calculations. Results: Of the 38,133 uterine cancer patients, 42.8% were diagnosed at <50 years (younger) and 57.2% at ≥50 years (older). Approximately, 77.1% identified as Non-Hispanic White (NHW), 7.0% as Non-Hispanic Black (NHB), 2.2% as Hispanic, and 3.7% as Non-Hispanic Asian/Pacific Islander (NHAPI). Approximately 29.1% patients had germline Lynch gene mutations with 16.5%, 28.8%, 36.1%, and 18.4% occurring in MLH1, MSH2, MSH6, and PMS2, respectively (p<0.001). Younger patients were more likely to have Lynch syndrome (9.6% vs 7.5%; p<0.001) and MLH1 (1.2% vs 0.8%; p<0.001) or MSH2 (3.1% vs 1.5%; p<0.0001) mutations compared to older patients. Regarding race, MLH1 mutations were found in 5.2% of NHW and NHAPI, 4.9% of Hispanics, and 2.2% of NHB (p<0.001). MSH2 mutations were most common among NHAPI (9.8%) and NHW (9.7%) followed by Hispanics (5.8%) and NHB (3.2%; p<0.001). MSH6 mutations were most common in NHW (12.8%) vs Hispanics (6.5%), NHAPI (6.3%), or NHB (4.5%; p<0.001). PMS2 mutations were highest among NHW (5.8%) followed by Hispanics (4.7%), NHAPI (4.4%), and NHB (2.9%; p=0.004). There were no differences in TMB (p=0.07), PDL1 (p=0.16), or MSI status (p=0.13) by age; however, younger patients had more HRD positivity (37.8% vs 30.9%; p<0.0001) vs the older group. Regarding race, 50.0% of NHAPI, 36.9% of NHW, 30.8% of Hispanic, and 11.6% of NHB patients had high TMB (p=0.004). There were no significant differences in tumor HRD status (p=0.3), MSI status (p=0.3), or PDL1 positivity (p=0.4) by racial group. Additionally, 6.8%, 6.6%, 6.3%, and 4.4% of Hispanics, NHW, NHAPI, and NHB were BRCA positive. BRCA2 mutations were more present among Hispanics (4.2%) vs NHW (3.7%), NHAPI (3.4%), and NHB (2.3%; p=0.02). There were no differences in BRCA1 (p=0.3) or PTEN (p=0.8) mutations by racial group. Hispanic patients had the most germline p53 mutations (2.0%) followed by NHAPI (1.5%), NHW (1.4%), and NHB patients (0.7%; p=0.01). PDL-1 inhibitors may be useful among NHB based on germline POLE mutations (4.3%) vs NHW (1.2%), Hispanic (1.1%), and NHAPI patients (0.8%; p<0.001). Conclusions: There are significant differences in germline testing results for women with uterine cancer by race/ethnicity and age, especially in Lynch genes which has implications for immunotherapy eligibility in the advanced and recurrent setting. Further work must be done to identify targetable mutations in minority populations.