Go to ucsc genome browser, and enter the coordinate chr9:131,939,104-131,939,143 (hg19). It's part of the gene IER5, going from right to left. If you take a look at the DNA sequence CAG, you will see below that it codes for V (Valine). But, doesn't CAG code for Gln, and GAC code for Asp? Why does CAG correspond to Val on the browser? 

Am I missing something terribly?
your gene is mapped on the reverse strand (3' -> 5') , the codon is not CAG but the complement: GTC  (valine)