Maize Genetics Barbara Mcclintock Completion of the Studs of the Allele Relations of Deficiency Mutants
ثبت نشده
چکیده
During this year studies were completed of 13 mendelizing recessive mutants associated with homozygous small terminal deficiencies of the short arm of chromosome 9. All 13 mutants arose independently following breakage of the short arm of a chromosome 9 which resulted, in each case, in deletion of a small terminal segment. Seven of these mutants gave a paleyellow seedling phenotype (designated pyd I to 7) and six gave a white seedling phenotype (designated wd I to 6). A detailed description of these mutants, their method of origin, and the extent of the deficiencies was given in Year Book No. 42. Completion of these studies consisted in (I) verifying the allelic if not identical nature of all 7 pyd mutants, (2) verifying the allelic nature of all 6 wd mutants, (3) determining that all 7 pyd mutants were allelic to and dominant over all 6 wd mutants, (4) determining that all 7 pyd mutants were not allelic to the recessive mutant yg-2 (yellow-green plants), and (5) determining that all 6 wd mutants were allelic and recessive to ~2-2. The results of the completed tests confirm the interpretation of the anomalous allelic relations given in the previous report.
منابع مشابه
A Secondary Trisome
** The ratio of the two arms of the No. 2 chromosome found in the writer's cultures is 1.0: 1.4 but McClintock has found certain strains of maize where the ratio is approximately 1.0:1.2. 1 McClintock, Barbara, Science, 69, 629 (1929). 2 Burnham, C. R., Proc. Nat. A cad. Sci., 16, 269-277 (1930). Rhoades, M. M., Ibid., 17, 694-698 (1931). Burnham, C. R., Proc. Sixth Int. Cong. Genetics, 2, 19-2...
متن کاملTransposable elements: Barbara McClintock and early experiments in maize In 1938 Marcus Rhodes provided the first genetic description of an unstable mutation, an allele of a gene required for the production of pigment in maize
In 1938 Marcus Rhodes provided the first genetic description of an unstable mutation, an allele of a gene required for the production of pigment in maize. This instability resulted in a variegated phenotype. Variegation describes irregular patterns of pigmentation and reflects changes in the expression of genes that control pigment production. Rhodes defined two genes required for this instabil...
متن کامل"The Origin and Behavior of Mutable Loci in Maize" (1950), by Barbara McClintock
"The Origin and Behavior of Mutable Loci in Maize," by Barbara McClintock, was published in 1950 in the Proceedings of the National Academy of Sciences [2] of the United States of America. McClintock worked at the Cold Spring Harbor Laboratory [3] in Laurel Hollow, New York, at the time of the publication, and in the article she describes her discovery of transposable elements in the genome [4]...
متن کاملBarbara McClintock on Defining the Unstable Genome.
It is with this prescient statement that Barbara McClintock began the discussion of her classic 1953 GENETICS article describing how so-called “extragenic” components, now known as transposons, could alter the function of nearby genes. Precisely 30 years later she would be the sole winner of the Nobel Prize in Physiology or Medicine for her scrupulous studies of unexpected phenotypic changes sh...
متن کامل