50 Pages

A Introducing Genetics

The rediscovery coincided with an appreciation that, during cell division, chromosomes in a cell are passed to the

two daughter cells exactly like Mendel's factors were in his breeding experiments. In 1902 and 1903, Theodor Boveri and Walter Sutton published this idea separately and almost at the same time (Boveri, 1902; Sutton, 1903). With this discovery, the chromosome theory was born; it was realized that the chromosomes in a cell carried the genetic information and that from one cell generation to the next the chromosomes were duplicated so that each daughter cell inherited a copy of the chromosomes and, hence, the genes. Some extraordinarily perceptive statements were made around this time. For example, in 1896, the cytogeneticist E.B. Wilson wrote:

These facts ... support [the idea] of the nucleus as the bearer of hereditary qualities. The chromosomal substance, the chromatin, is to be regarded as the physical basis of inheritance ... and thus we reach the remarkable conclusion that inheritance may be, perhaps, effected by the physical transmission of a particular chemical compound from parent to offspring.