For a significantly oversimplified example of this type of processing consider searching PubMed for the terms breast cancer and BRCA1. The initial search returns 50 articles, as compared to 21 for breast cancer with BRCA2, 6 with PIK3CA, 1 with TOX3, and 0 for MC4R or CLC1 associations. This evidence concerns the gene BRCA1 and breast cancer.