In the sentence extracted from biomedical literature, identify all the chemical entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="chemical"> to denote a chemical.

### Input Text: CONCLUSION : Our results did not lend strong support to the view that the genetic variation of the DRD2 gene plays a major role in the individually variable adverse effect induced by chlorpromazine , at least in Chinese patients with schizophrenia .
### Output Text:
CONCLUSION : Our results did not lend strong support to the view that the genetic variation of the DRD2 gene plays a major role in the individually variable adverse effect induced by <span class="chemical">chlorpromazine</span> , at least in Chinese patients with schizophrenia . 