a) Distribution of HMMER bit scores for the database search of EH1hox HMM against the combined proteomes of human, D. melanogaster and C. elegans. Counts from scores from transcription factors (see methods) have been coloured red – i.e. the proportion of a bar coloured red is equal to the proportion of transcription factors. Scores from proteins containing a homeobox domain (interpro accession IPR001356), from which the EH1hox HMM was derived, have been excluded, b) as for 'a', but rescaled to show region of biological relevance. High scoring hits are greatly enriched in specific transcription factor families. For scores ≥ 5.0 bits, there are 68 transcription factors and 142 non-transcription factors; for scores <5.0 bits, 3075 transcription factors and 51513 non-transcription factors giving a chi-square test p-value statistic of P < 0.0001 – the statistical significance is discussed more fully in the text.