By plotting the sensitivity and specificity of classifying BRCA1/2 biallelic alteration vs. wild type using genomic LoH, the authors found a cutoff of >17.6% genomic LoH for BTC, which is very close to the >16% genomic LoH which was used in the ARIEL trial of rucaparib in ovarian cancer [106]. This evidence concerns the gene BRCA1 and ovarian cancer.