BARD1 and neuroblastoma: Relative expression of BARD1 FL and BARD1 β isoform in MKI subgroups are shown in Figure 3B. In the examined NB group, there was 80% (n = 71/89) neuroblastoma type in three histological subtypes: differentiating 32.6%, poorly differentiated 49.3%, and undifferentiated 9.9%.