For a later article see: M.Q.Zhang and T.G.Marr Fission yeast gene structure and recognition. Nucl. Acid Res. 22: 1750 1994 P. Garrison Preston N. Garrison, Ph.D. UTHSCSA-Biochem. Dept. Insert the usual disclaimers here. 7703 Floyd Curl Dr. San Antonio, TX 78284-7760 210-567-3702 garrisonp at arwen.uthscsa.edu