* FTSEurofirst 300 down 0.6 percent, off lows
* Glencore claws back some ground from Monday's sell-off
* European biotech stocks hit by drop in U.S. counterparts
* Wolseley slumps after cutting outlook (Updates with closing prices)
By Alistair Smout and Sudip Kar-Gupta
LONDON, Sept 29 (Reuters) - European shares partially recovered from an early drop on Tuesday, supported after battered miner Glencore halted a slide in its share price, although top indexes lingered near their lows for 2015.
The pan-European FTSEurofirst 300 index closed down 0.6 percent at 1,336.34 points, having been as much as 1.7 percent lower in early deals.
The index fell more than 2 percent on Monday, and Tuesday morning's early retreat took it just 0.8 percent away from its low for 2015, set in August.
Glencore surged 16.9 percent, its biggest single session gain, having dropped 30 percent in the previous session to an all-time low.
It extended earlier gains after the mining and trading company declared its business remained "operationally and financially robust".
Several brokers said worries over the commodities and mining company's debt pile were overdone.
"Momentum is against Glencore, but fundamentally the stock is very cheap, and we don't think that is justified," said Ankit Gheedia, equity and derivatives strategist at BNP Paribas.
He said the drop in the broader market in recent weeks had also been exaggerated. "Fundamentally the falls have gone too far, but the momentum tends to persist for a bit longer, even while the fundamentals are fine."
The FTSEurofirst 300 is down around 20 percent since April, when it touched its highest level since 2000. Germany's DAX hit a record high of 12,390.75 points in April but is now some 24 percent below those levels.
Stock markets have lost ground in the past few months partly due to signs of a slowdown in China, which has also hit the commodity sector as China is a major consumer of metals and oil.
The prolonged plunge in metals prices has been one of the reasons behind Glencore's stock market slump.
U.S. bank Citigroup said Glencore should even consider going private via a management buyout if the market turmoil continued, and kept a "buy" rating on Glencore shares.
The STOXX Europe 600 Health Care index posted the biggest sectoral decline, dropping 1.8 percent after U.S. pharmaceutical and biotech stocks fell overnight.
The U.S. biotech sector was hit after U.S. Democratic lawmakers on Monday denounced "massive" price increases for two heart drugs from Valeant Pharmaceuticals.
In Europe, British healthcare group Shire was down by 3.2 percent while Switzerland's BB Biotech retreated 4.8 percent.
Building supplier Wolseley fell 12.5 percent after lowering its second half revenue growth forecast, saying it expected markets in North America and Britain to remain challenging.
"The ... drop is probably an over-reaction. The trouble is that volatility breeds volatility," Jasper Lawler, market analyst at CMC Markets, said in a note, citing the wild swings in previous sessions in Glencore.
"When Glencore stock plunges 27 percent, it creates an expectation that there could be a double digit drop on any company news."
Today's European research round-up (Additional reporting by Lionel Laurent; Editing by Alison Williams)