Stanford University

Date:
1979-1980
Reference:
PP/CRI/E/1/28/6
Catalogue details

Licence: In copyright

Credit: Stanford University. Source: Wellcome Collection.

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    GENES AND CHROMOSOMES A MOLECULAR VIEW OF CHROMOSOMES David S. Hogness The dna in a chromosome of a higher organism consists of a long molecule, often several centimeters in length. Molecu lar cloning by recombinant dna techniques has provided the means for amplifying and isolating any given segment of these long dna molecules—allowing, for the first time, the molecular analysis both of individual genes and of the general organization of genetic information in higher or ganisms. We have used this approach to analyze the genes and chromosomes of the fruit fly favored by the classical geneticists, Drosophila mdanogaster. That analysis has pro duced surprises, such as genes that jump about the chromo somes, and has provided a basis for determining the molecular mechanisms underlying the genetic control of development. GENES AND CHROMOSOMES TRANSPLANTING AND MANIPULATING GENES IN BACTERIA Stanley N. Cohen The ability to clone and manipulate dna molecules intro duced into bacteria has enabled the analysis of gene func tion and organization at a level that was not previously possible. Such experiments require a vehicle or vector capa ble of propagating dna in a foreign host, a method of linking exogenous genes to the vector, a means of introduc ing the composite dna molecules into living cells, and procedures for identifying cells in the population that have acquired the desired constructs. dna cloning methods have yielded important new insights about the biology of both prokaryotes and eukaryotes and have provided valu able data about regulatory mechanisms that accomplish ex pression of genes in their original hosts or in new biological environments. While such manipulations are methodologi cally novel, they have natural counterparts in the transpos- able genetic elements that join together structurally and ancestrally unrelated dna segments within living cells. References: Cohen S. N., The manipulation of genes, Sci. Am. (1975) 233 (1): 25-33. Cohen S. N., and Shapiro J. A., Transposable genetic elements, Sci. Am. (1980) 242: 36-45.
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