Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_39 ( mutated_from VARCHAR, plant_patent_number VARCHAR )

### Question ###
What's the mutated having a patent number of US plant patent 9645?

### Accurate SQL ###

SELECT mutated_from FROM table_name_39 WHERE plant_patent_number = "us plant patent 9645"