* Trading volumes low as Ramadan, summer holidays loom

* Shuaa jumps as lay-offs spur stake sale hopes

* GFH Financial rises before briefing

* Saudi's Al Yamamah Steel ends post-listing rally

* Medinet Nasr continues climbing in Egypt

By Andrew Torchia

DUBAI, May 24 (Reuters) - Most Gulf stock markets rose on Tuesday but trading volumes were small as some investors stayed away because of the approach of the holy month of Ramadan and summer holidays, when activity tends to decrease in some bourses.

Dubai's index .DFMGI spent most of the day little changed but closed 1.0 percent higher after a surge in the final half-hour.

Investment bank Shuaa Capital SHUA.DU jumped 3.7 percent in unusually heavy trade after sources told Reuters that it cut about 15 percent of its workforce at the end of last week, ahead of a possible sale of a stake in the company by Dubai Group. urn:newsml:reuters.com:*:nL5N18K0ER

Dubai Group mandated Emirates NBD in April to arrange a sales process for its 48 percent stake in Shuaa. There is speculation in the market that a major financial firm in Dubai or the Middle East could buy the stake; Shuaa did not respond to requests for comment.

GFH Financial GFH.DU , the most heavily traded stock, added 2.1 percent after it invited its shareholders and investors to attend a briefing by senior management in Dubai on Wednesday afternoon on its future prospects.

Saudi Arabia's index .TASI rose 0.8 percent in its thinnest volume since early January, with the petrochemical sector index .TPISI climbing 1.1 percent.

But Al Yamamah Steel 1304.SE , which had jumped 15 percent in its first two days of trade since listing on Sunday, fell back 2.4 percent.

Abu Dhabi's index .ADI rose 0.6 percent. Abu Dhabi Commercial Bank ADCB.AD climbed 1.5 percent but seven of the 10 most heavily traded stocks were flat or lower.

Qatar .QSI fell 0.2 percent as real estate firm Ezdan ERES.QA lost 0.9 percent but drilling rig provider Gulf International Services GISS.QA , again the most heavily traded stock, surged 2.6 percent.

Egypt's index .EGX30 rebounded 1.1 percent, buoyed by Global Telecom GTHE.CA , which added 1.3 percent.

Real estate firm Medinet Nasr MNHD.CA , which rose 2.0 percent on Monday when it reported that quarterly net profit jumped 90 percent, gained a further 1.7 percent after saying it was considering taking out a 1 billion Egyptian pound ($113 million) loan to speed up development of one of its plots. urn:newsml:reuters.com:*:nL3N18L2S3



* The index .TASI rose 0.8 percent to 6,475 points.


* The index .DFMGI gained 1.0 percent to 3,248 points.


* The index .ADI rose 0.6 percent to 4,222 points.


* The index .QSI fell 0.2 percent to 9,665 points.


* The index .EGX30 rose 1.1 percent to 7,497 points.


* The index .KWSE gained 0.2 percent to 5,323 points.


* The index .MSI fell 0.2 percent to 5,937 points.


* The index .BAX edged up 0.1 percent to 1,101 points.
 (Editing by William Hardy) ((andrew.torchia@thomsonreuters.com)(+9715 6681 7277)(Reuters Messaging: andrew.torchia.thomsonreuters.com@reuters.net))