Each culture was derived from between 6 and 12 mice of c. 6 weeks old and of mixed sexes. Sex ratios in each batch varied. Triplicate cultures, from the same line but of different passage numbers, were used for RNA collection. Quantile normalisation of probe-level values was performed, and data for all probes mapping to the same Entrez GeneID were merged as means. No further adjustment of the data was done.