LONDON, Dec 8 - The dollar extended its slide to a record low beyond $1.22 per euro on Monday as a breach of an option strike triggered further selling in the greenback. By 1145 GMT the dollar had fallen to $1.2208 , hitting a record low for the seventh consecutive session. "There was a knock out (option) level at $1.22, there must have been some defense for most of the morning, that's just broken through and when that happened it triggered a few stops," a U.S. bank dealer said. The dollar has been under pressure after weaker than expected U.S. jobs data last week. Concerns about the United States' ability to fund its huge current account deficit have also dampened sentiment.//