* Myriad Genetics Inc., of Salt Lake City, received patent No. 5,683,880, covering a method for rapidly determining whether known genetic markers are linked to a disease of interest, "an important step in Myriad's gene discovery process," the company said.

* Protein Polymer Technologies Inc., of San Diego, received a notice of allowance covering recombinantly produced proteins that consist of relatively short sequences of amino acids found to be repeated in natural proteins.

* Receptagen Ltd., of Edmonds, Wash., received patent No. 5,688,504, covering methods for inhibiting cellular uptake of vitamin B12, which is required for cellular division.

* Shaman Pharmaceuticals Inc., of South San Francisco, received two patents — Nos. 5,681,958 and 5,691,386 — covering the use of cryptolepine analogues and triterpenoid compounds with hypoglycemic activity in the treatment of diabetes.

* Sugen Inc., of Redwood City, Calif., received two patents — Nos. 5,700,822 and 5,700,823 — covering the use of its lead therapeutic, SU101, and related compounds in treating patients with solid tumors characterized by inappropriate platelet-derived growth factor receptor activity.

* Thermogenesis Corp., of Rancho Cordova, Calif., received a notice of allowance for a patent covering aspects of its CryoSeal System, which produces therapeutic proteins from blood plasma.

* Titan Pharmaceuticals Inc., of South San Francisco, received patent No. 5,702,700, covering a method for treating Parkinson's disease by implanting Sertoli cells directly into the affected area of the brain without the need for immunosuppression. Sertoli cells secrete a variety of growth factors.

* Vical Inc., of San Diego, received patent No. 5,703,055, covering the firm's method of naked DNA vaccination, which involves direct injection into any tissue of DNA sequences combined with lipids.

* Visible Genetics Inc., of Toronto, received a notice of allowance for a patent covering a method of identifying patient test samples that combines genetic analysis and barcode technology.