Glucosinolates play important roles in plant defense against herbivores and microbes, as well as in human nutrition. Some glucosinolate-derived isothi-ocyanate and nitrile compounds have been clinically proven for their anti-carcinogenic activity. To better understand glucosinolate biosynthesis in Brassica rapa, we conducted a comparative genomics study with Arabidopsis thaliana and identified total 56 putative biosynthetic and regulator genes.