ARID1A and neoplasm: The insertion of transposon in the Arid1a gene resulted in a 60% reduction of Arid1a expression, and reduced tumour free survival (SB:Ptenfl/flArid1aINT median 226 days vs SB:Ptenfl/flArid1aWT 293 days, p = 0.02),with elevated rates of metastasis (SB:Ptenfl/flArid1aINT 75% lung metastasis rate vs 17% SB:Ptenfl/flArid1aWT, p < 0.001).