** Merck MRCG.DE falls 4% to 101.05 euros
** Stock set for worst day since May; among worst performers on German blue chip index .GDAXI
** German firm posts Q2 revenue of 5.2 bln euros, adjusted EBITDA of 1.46 billion euros, both below analysts' consensus provided by co
** J.P. Morgan says, "While the Q2 miss will be disappointing for some, it is largely related to one-time items in Electronics, which are offset by corresponding one time positive in Healthcare to come in H2"
** YTD MRCG loses 27%
(Reporting by Paolo Laudani)
((Paolo.laudani@thomsonreuters.com))