RSPO3 and in situ carcinoma: The distance between the activating MMTV RIS and the target CIS gene ranged from 100 bp to greater than 200Kb (See Supplementary Figure 1), for example: Rspo3, 246Kb (Tumor#5447); Phf19, 663 Kb (Tumor#6749) and Tacstd2, 716Kb (Tumor#7856).