Biotech and tech stocks have been in a slump for the past three weeks, evidenced in part by the 3.1 percent drop in the Nasdaq Composite — the worst one day percentage decline, according to MarketWatch, since November 2011. The Nasdaq Biotech Index and the iShares Nasdaq Biotechnology ETF both dropped 5.6 percent.

“Techs and biotechs really haven’t cracked yet,” said Uri Landesman, president of hedge fund Platinum Partners, told MarketWatch, adding that these stocks have much further to decline. “I think it’ll happen and people will be surprised how much they can really go down. So if they crack, it could get a lot worse. It wouldn’t shock me if July Fourth weekend we wake up to a 1600 S&P 500.”

Indeed, most publicly traded San Diego biotechs posted significant declines April 10. For example, Illumina Inc. dropped about 7 percent, or $10.10, closing day trading at $135.74. Its 52-week high was $183.30. Isis Pharmaceuticals Inc. dropped about 9 percent to $35.98 April 10, and Ligand Pharmaceuticals Inc. dropped 8.6 percent to $63.93.