How many n are listed for 0.6% r1b1a2 (r-m269)?
CREATE TABLE table_21481509_4 (
    COUnT VARCHAR,
    r1b1a2__r_m269_ VARCHAR
)
SELECT COUnT AS n FROM table_21481509_4 WHERE r1b1a2__r_m269_ = "0.6%"
Below are sql tables schemas paired with instruction that describes a task. Using valid SQLite, write a response that appropriately completes the request for the provided tables. ### Instruction: How many n are listed for 0.6% r1b1a2 (r-m269)? ### Input: CREATE TABLE table_21481509_4 (
    COUnT VARCHAR,
    r1b1a2__r_m269_ VARCHAR
) ### Response: SELECT COUnT AS n FROM table_21481509_4 WHERE r1b1a2__r_m269_ = "0.6%"