Basikaryotype and Its Analysis
1940 Volume 10 Issue 4 Pages 529-538
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1940 Volume 10 Issue 4 Pages 529-538
The conception of the basic number of chromosomes has been established by the studies made on the chromosome numbers during the last four decades, and a basic number and morphology of the chromosomes composing it have been investigated by the method of karyotype analysis. We propose applying the term basikaryotype to such a chromosome type which is specific to individuals or groups, corresponding in number to the basic number, and viewed from the stand-point of their morphology. The chromosome behavior in meiosis has to be observed in order to pursue the investigation of the phylogenetic relation of the basikaryotypes. The criterion of the homology of chromosomes is assumed to be the pairing of the chromosomes. By this method the existente of those karyotype alterations which were either expected to have occurred or are not capable of being distinguished by the karyotype analysis may be established on karyogenetical grounds. This method is here called a basikaryotype analysis.
Comparing the basikaryotype analysis with the genome analysis, the former originated in the karyotype, while the latter started from hybridization as a premise. With the recent advances in the study of chromosome morphology the conception of the genome has come to take the karyotypes into consideration, and accordingly the new stand-point has been developed to facilitate discussion of the genetical connection of individuals or groups based upon the karyotype. The karyotype analysis is different from the genome analysis in that the former enables one to presume the relationship between the forms which can not be hybridized with each other, while it further enables determination of the basikaryotypes. The basikaryotypes may be detected in the forms in which the karyotype analysis was carried out. Some examples have been given (p. 533). The homology of the basikaryotypes may be traced by the method of basikaryotype analysis here proposed. An example of this method in the case of Aloinae was described (p. 534).
