ROTIFER GENETICS - INTEGRATION OF CLASSIC AND MODERN TECHNIQUES

Rotifer genetics has a long but sporadic history. There have been 4 ma jor periods of research activity: (1) determining the environmental co ntrol of sexuality with inferences regarding genetics - early 1900's; (2) exploring the relationship between chromosome numbers and the roti fer life cycle - 1920's; (3) physiological and developmental genetics - 1960's; and (4) theoretical and experimental population genetics lat e 1970's. With newly developed molecular techniques, in conjunction wi th more traditional approaches, integration of these fields is beginni ng. Examples include investigation of gene expression involved in sexu al reproduction by isolating glycoproteins responsible for mate recogn ition. Improvement of techniques for chromosome analysis has made it p ossible to verify haploidy in males and led to the discovery of polypl oidy. The role of specialized proteins in the stress response is being elaborated with an accompanying search for the genetic elements which control them. Most recently the polymerase chain reaction (PCR) has b een used to amplify ribosomal genes, and is a first step in using DNA sequences to define evolutionary relationships among the Rotifera.