ZymoGenetics, the Seattle-based biotech company, said today it has raised about $79 million after expenses from an underwritten stock offering. The company (NASDAQ: ZGEN) sold 14 million shares at $6 apiece, and also offered its underwriters a 30-day option to buy another 2.1 million shares. Leerink Swann was the sole book-running manager of the offering, while Wedbush Morgan Securities, William Blair & Co., Canaccord Adams, and McAdams Wright Ragen served as co-managers. The price represents an 11 percent discount for investors from yesterday’s close of $6.77 a share. ZymoGenetics had about $103 million of cash and investments on hand as of the end of September, its most recent financial report.