Unclear grammar of terminator (SO:0000141)

[greg-sharpe]

terminator (SO:0000141) has the following definition:
The sequence of DNA located either at the end of the transcript that causes RNA polymerase to terminate transcription.

I think that this is a grammatical mistake, and should be one of:
"... at either end of the transcript..."
"... either at the end of the transcript that causes... or [other location]"