SHANGHAI, March 14 (Reuters) - China stocks held steady on Thursday as a rally in biotech stocks offset weakness in gaming and chip companies. Hong Kong shares declined, dragged by Wuxi Apptec, as concerns over geopolitical risks persisted.

** China's blue-chip CSI300 Index and the Shanghai Composite Index were roughly flat by the lunch break. Hong Kong's benchmark Hang Seng Index was down 0.6%.

** CSI 300 Healthcare Index rose as much as 3.6% in early trade on market talks of potential policy support for China's biotech sector.

** Shares of China's pharmaceutical giant Hengrui and biotech company Beigene jumped 5.4% and 8.6%, respectively.

** Shares of clinical trials and contract research firms also rose, with Tigermed Consulting up to a maximum of 20%.

** In contrast to the broad healthcare stocks' rally, sentiment over Wuxi Apptec and Wuxi Biologics weakened further as a U.S.-based biotech trade association is taking steps to "separate" from Chinese member Wuxi AppTec, sending both shares down more than 8%.

** CSI Non-ferrous Metal Index and Hang Seng Composite Materials Index rose as much as 3.9% and 5.9%, respectively.

** Chinese top copper smelters on Wednesday came to a rare agreement to jointly embark on production cuts at some loss-making plants as they seek to cope with a shortage of raw material, according to sources with knowledge of the plans.

** Gaming and semi-conductor shares dropped 3% and 1.2%, respectively.

** Foreign capital net buying via the northbound link of the Stock Connect programme logged 3.1 billion yuan ($431 million), on track for the fifth consecutive session of inflows.

** Analysts at HSBC said in a note that current cheap valuations, low foreign participation rate, and policy stimulus are among the reasons that would attract foreign investors to China's onshore shares.

($1 = 7.1925 Chinese yuan renminbi) (Reporting by Shanghai Newsroom; Editing by Mrigank Dhaniwala)