Bionano Genomics Inc. BNGO, -19.20% said Friday it has priced an underwritten public offering of 29 million shares at $3.05 a share. The stock closed Thursday at $5.00. The genome analysis company has granted the underwriters -- Oppenheimer & Co., which is sole bookrunner, while BTIG acted as lead manager and Ladenburg Thalman and Maxim Group acted as co-managers -- a 30-day option to acquire an additional 4.3 million shares at the offering price. The stock, which has been volatile in recent sessions, slid 18% premarket, but is up more than 300% in the last 12 months, while the SPDR S&P Biotech ETF XBI, -1.47% has gained 58% and the S&P 500 SPX, -0.39% has gained 17.5%.