Book contents
- Frontmatter
- Contents
- List of figures
- Acknowledgments
- Introduction
- PART I FROM REPRODUCTION AND GENERATION TO HEREDITY
- PART II FAKTOREN IN SEARCH OF MEANING
- PART III THE CHROMOSOME THEORY OF INHERITANCE
- PART IV GENES AS THE ATOMS OF HEREDITY
- 8 Characterizing the gene
- 9 Analysis of the gene by mutations
- 10 From evolution to population genetics
- PART V INCREASING RESOLVING POWER
- PART VI DEDUCING GENES FROM TRAITS, INDUCING TRAITS FROM GENES
- PART VII WHAT IS TRUE FOR E. COLI IS NOT TRUE FOR THE ELEPHANT
- Concluding comments
- Bibliography
- Index
8 - Characterizing the gene
Published online by Cambridge University Press: 07 August 2009
- Frontmatter
- Contents
- List of figures
- Acknowledgments
- Introduction
- PART I FROM REPRODUCTION AND GENERATION TO HEREDITY
- PART II FAKTOREN IN SEARCH OF MEANING
- PART III THE CHROMOSOME THEORY OF INHERITANCE
- PART IV GENES AS THE ATOMS OF HEREDITY
- 8 Characterizing the gene
- 9 Analysis of the gene by mutations
- 10 From evolution to population genetics
- PART V INCREASING RESOLVING POWER
- PART VI DEDUCING GENES FROM TRAITS, INDUCING TRAITS FROM GENES
- PART VII WHAT IS TRUE FOR E. COLI IS NOT TRUE FOR THE ELEPHANT
- Concluding comments
- Bibliography
- Index
Summary
Johanssen wished to discern the phenotype from the genotype (Johannsen, 1909). “Genes,” however, became what geneticists concluded Mendelian Faktoren had been. Were genes hypothetical constructs, autonomous structural entities or loci of differential functional emphases along an integral chromosome? Or, did all that not matter and genes were simply intervening variables, helpful entities for experimental work (see Chapter 4)?
Strictly speaking, there are no hypothesis-free concepts, and the distinctions between hypothetical constructs and intervening variables that proved very helpful historiographically, are more problematic when one attempts to apply them to personal conceptions. Whether we wish it or not, our concepts “are constructions in thought representing historically an immense amount of intellectual work … the scientific hypothesis does not come after the numerical data but before them” (Woodger, 1967, 366). Morgan, like Johannsen, insisted on presenting genes as intervening variables, with no hypothesis about the nature of the “something.” As late as in his Nobel talk he asserted:
Now that we locate [the genes] in the chromosomes are we justified in regarding them as material units; as chemical bodies of a higher order than molecules? Frankly, these are questions with which the working geneticist has not much concerned himself, except now and then to speculate as to the nature of postulated elements. There is no consensus of opinion amongst geneticists as to what genes are – whether they are real or purely fictitious – because at the level at which the genetic experiments lie, it does not make the slightest difference whether the gene is a hypothetical unit, or whether the gene is a material particle.
Morgan (1943b, 315)- Type
- Chapter
- Information
- Genetic AnalysisA History of Genetic Thinking, pp. 128 - 140Publisher: Cambridge University PressPrint publication year: 2009