MICHIGAN - US biotech firm, Kraig Biocraft Laboratories, which develops genetically modified spider silk-based fibres, has announced the creation of four new lines of transgenic silkworms. The company says the new transgenics are based on "a new set of the company's most complex protein designs to date," and are targeted for applications in performance apparel, medical, and ballistic protection. Spider silk is antimicrobial, hypoallergenic, and completely biodegradable.