Figure 3

Clusters of transcripts (left) derived from the testicular cancer dataset and (right) associated expression profiles (average signal per gene or cluster). The individual tumours (represented along the y-axis) were grouped by mixed (green in upper bar) or pure histological subtype (red in upper bar) and then by components present (coloured blocks in lower bar) a) Haemoglobin cluster containing data derived from 5 probesets designed to HBA1 and 3 designed to HBB. The haemoglobin locus cluster is found to be present in many human expression datasets and is often unconnected to any other genes. b) Cluster of somatotrophin genes whose expression is normally tissue specific and limited to pituitary and placenta, shown here to be expressed predominately in tumours containing elements of choriocarcinoma, a tumour formed of malignant trophoblast cells, the normal equivalent of which are involved in placenta formation. c) HOX genes found to be expressed only in two teratomas with secondary carcinomatous transformation. Interestingly one of these tumours shows a high degree of up regulation of one group of primarily HOXB genes and the other a mix of HOXA/C/D genes.