The most common and most likely answer to this crossword clue is the 4 plus 10 letter word BEAT GENERATION
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More clues leading to the result BEAT GENERATION
- US writers use drum and bass for this?
- Mix DNA sequence a lot in movement of the young
- Teenager a bit zonked working for Ginsberg etc
- Role of drum machine in countercultural movement
- Drop-outs in fifties obtain teenager to groom
- Bohemian writers begin to eat near rocks
- Ginsberg, Kerouac etc all in reproduction
Buddy explains!

The straight part
We know that "US writers" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case us writers = beat generation.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.