However, some studies have reported that heterozygous pathogenic or potentially pathogenic germline mutations in DNA repair genes, for example, FANCC, FANCA, ERCC2, and BRCA1, may contribute to Ewing sarcomas because they enable the occurrence of DNA breaks leading to oncogenic gene fusions, such as EWSR1::ETS (12–15). The gene discussed is BRCA1; the disease is Ewing sarcoma.