In November 1970, approximately 90 cytogeneticists convened at Colorado Springs, Colo, to participate in a conference titled "Perspectives in Cytogenetics."1 The purpose of the conference sponsored by the National Institute of Child Health and Human Development was to review the remarkable advances in cytogenetics of the preceding decade and to peer into the decade ahead. The buoyant atmosphere that reflected the satisfaction of past accomplishment was soon displaced by the sense of anticipation for progress in the 1970s.
The enthusiasm for the next decade was in great measure due to presentations describing new methods for the precise identification of all members of the human chromosome complement. "Breakthrough" was the cliché of the day.
Caspersson and Zech2 presented, in extensive detail, their method for quinacrine fluorescent labeling and identification of human chromosomes. Their conclusion that each and every member of the human chromosome complement could be clearly identified was dramatically