The Sashelp.Comet data set provides information from the following experiment. Twenty-four male rats were divided into four groups. Three groups received a daily oral dose of a 1,2-dimethylhydrazine dihydrochloride in three dose levels (low, medium, and high, respectively); the fourth group was a control group. Three additional animals received a positive control. Cell suspensions for each animal were scored for DNA damage by using a comet assay. The following steps display information about the Sashelp.Comet data set and create Figure B.5:

title 'Comet Data';
proc contents data=sashelp.Comet varnum;
   ods select position;
run;

title 'The First Five Observations Out of 4050';
proc print data=sashelp.Comet(obs=5);
run;