MSH2 and neoplasm: In two of these tumours read numbers of downstream exons were even significantly <50% of controls, supporting additional perturbation of the trans-allele, as expected for tumour suppressor genes (tumours T1345 and M2532, 88% and 96% downregulation of MSH2 (ref. 33) and STARD7 (ref. 34), respectively; Fig. 1c).