** HSBC down 4.5 pct, bottom of the Stoxx and the FTSE 100, after saying FY pretax profit rose to$18.87 bln, short of analysts' expectations of $21.8 bln
** Co adds under investigation by U.S. regulators relatingto hiring practices of people tied to government officials inAsia; warns of uncertain environment particularly in top marketChina
** Shares set for worst day since Feb. 11, with half of co'sdaily avg volume gone through by 0910 GMT
** Co only European bank in the red, sector up 1 pcton the day and up 8 pct since hitting 3-1/2 yr lows two weeksago
** Co's Hong Kong-listed shares closed down 2 pct
** European banks down 23 pct YTD, HSBC down 16 pct; sharesin banks have been hammered this year as concerns over exposureto falling oil prices and fears regarding the health of theglobal economy take their toll (venkateshasoumithri.mamidipudi.thomsonreuters.com@reuters.net)