POLE2 and Fanconi anemia: Similar to those in groups f and g, the hub genes (pole2, rfc3, pole, pcna, pold1, pole3, rpa2, rfc5, lig1, and rpa1) in groups c, f, and g were clustered into nucleotide excision repair, cell cycle, DNA replication, base excision repair, mismatch repair, and fanconi anemia pathway (Figure 6E,F).