Looks like they are exit scamming. They already transferred 200k DNA from their wallet to Qtrade to dump it. I have no strong proof but it looks very suspicious:

Qbtc wallet:
https://scan.idena.io/address/0x1f96445BE4D941934277CCe0C02D9EA8c9cc02f5
Qtrade wallet:
https://scan.idena.io/address/0x83B8A2F9Bd1bE7f1fB496ec91eB0C6983cD38725

Qtrade deposits from Qbtc:
https://scan.idena.io/address/0x725Cd7c7f921D157ACF49f7f1689265D473B0e28
https://scan.idena.io/address/0x9dd82a9e7b8C83f3A19aF1cc10B382Cdb9449510

Most transfers from QBTC to Qtrade are done by those 2 qtrade deposit address (no deposit from Qtrade to Qbtc so most likely its not arbitraging)

Qtrade reports 30k DNA daily volume with 2.5 mln coins on their wallet
QBTC reports 2 000k DNA daily volume with 0,08mln coins on their wallet.

I would suggest withdrawing from QBTC as soon as it is possible to safe funds and to stop them from dumping our coins on us.

Most likely they are major bear that push price down. Hopefully there are only 80k left (from 300k)