Black women of African ancestry experience more aggressive breast cancer with higher mortality rates than White women of European ancestry. Although inter-ethnic germline variation is known, differential somatic evolution has not been investigated in detail. Analysis of deep whole genomes of 97 breast tumors, with RNA-seq in a subset, from indigenous African patients in Nigeria in comparison to The Cancer Genome Atlas (n=76) revealed a higher rate of genomic instability and increased intra-tumoral heterogeneity as well as a unique genomic subtype defined by early clonal GATA3 mutations and a 10.5-year younger age at diagnosis. We also found evidence for non-coding mutations in two novel drivers (ZNF217 and SYPL1) and a novel INDEL signature strongly associated with African ancestry proportion. This comprehensive analysis of an understudied population underscores the need to incorporate diversity of genomes as a key parameter in fundamental research with potential to tailor clinical intervention and promote equity in precision oncology care. ### Competing Interest Statement K.P.W. is a Scientific Advisor and Fellow at Tempus. O.I.O is co-founder at CancerIQ and serves as Scientific Advisor at Tempus. All other authors declare no competing interest.

Download data

• Downloaded 278 times
• Download rankings, all-time:
  • Site-wide: 89,918
  • In genomics: 5,635
• Year to date:
  • Site-wide: 31,122
• Since beginning of last month:
  • Site-wide: 24,707

Altmetric data

Downloads over time

Distribution of downloads per paper, site-wide