Distal squamous cell metaplasia score*.

*Squamous cell metaplasia score was generated by adding the metaplasia score and two extent scores.**Extent is for the distal half of the distal colon where longitudinal mucosal folds start. Two extent scores are included in the total squamous metaplasia score. Extent 1 = % of distal colon affected in any manner; Extent 2 = % percent of distal colon affected by the most severe score.***The highest grade dysplasia noted in the Smad3−/− studies was 2 (low grade) but the higher scores are included here for completion.