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Introduction1
SYMPOSIUM: CYTOGENETICS - TECHNIQUES, RESEARCH, AND PRACTICAL IMPLICATIONS Introduction 1 RAMAKRISHNA P. REDDY Peterson Farms, Inc., Decatur, Arkansas 72722 (Received for publication January 22, 1981) (Key words: cytogenetics, cytogenetic research, avian cytogenetics, chromosomes, embryos) 1981 Poultry Science 60:1353-1354
1 Presented at the 69th Annual Meeting of the Poultry Science Association as a part of a symposium entitled "Cytogenetics—Techniques, Research, and Practical Implications" sponsored by the Genetics section.
sium, "Cytogenetics—Techniques, Research, and Practical Implications" was organized. The objectives of this symposium were to review the avian cytogenetic research being done in the country and to understand how this branch of genetics could interface or complement other disciplines of poultry research. This was necessary because cytogenetic research involving domestic poultry has been escaping the attention of several poultry scientists. The four invited speakers are well recognized in the field and provided an overview of the importance of cytogenetic research. In the first paper, "Detection of Normal and Aberrant Chromosomes in Chicken Embryos and in Tumor Cells," S. E. Bloom of Cornell University reviewed the techniques for studying chromosomes and summarized his work on the frequency of chromosomal aberrations in various poultry populations and virus-induced tumor cells. His studies interfacing both cytogenetics and immunogenetics may pave a way in developing populations resistent to certain diseases, which the breeders are looking for. The second paper, entitled "Cytogenetic Studies of Embryos Developing Parthenogenetically in Turkeys" by Ko Harada and E. G. Buss of Pennsylvania State University, was presented by E. G. Buss. This paper included their most recent study on chromosome behavior in mosaic embryos of turkey and chickenturkey hybrids. N. S. Fechheimer of Ohio State University presented data on the frequency of chromosomal aberrations in chicken populations of commercial importance. In this third paper, "Origins of Heteroploidy in Chicken Embryos," he demonstrated the mode of origin of heteroploidy by using marker chromosome techniques. This work may arouse some interest in commercial breeders because of higher aberration rate in
1353
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on May 11, 2015
Since the development of cell theory, the most significant discovery in biology was the theory of chromosomal basis of hereditary by Morgan et al, (1915) by demonstrating a parallelism between abnormal genetic phenomenon and corresponding chromosomal aberrations. While the cytogenetic research advanced dramatically with various species, including humans, such work with poultry experienced a lag, primarily due to lack of proper techniques for identification and further characterization of the chromosomes as well as to the fact that aves have a rather large number of microchromosomes. Cytogenetic methods are useful not only for the routine identification of chromosomes and linkage relationships, but also for detection of pathological conditions in cells. Structural or numerical alterations in chromosome complement may be of use in sex-limited inheritance and increasing the genetic variation in a population. Interspecific transfer of genetic material, cell hybridization, polyploidization, and chromosome mediated gene transfer could offer practical advantages in commercial poultry production as we approach genetic plateaus. Karyological investigations also serve as a model for analysis of various etiological agents contributing to early embryonic mortality and developmental defects. As a part of total genetics program at the 69th annual meeting of the Poultry Science Association held at Purdue University a sympo-
1354
REDDY
broiler populations undergoing selection for broiler traits. In the final paper, "Marker Chromosomes and G-Banding for Location of Genes in the Chicken," R. N. Shoffner of the University of Minnesota provided the technique of combination of marker chromosome and G-banding differentiation in locating the blue egg gene and the gene involved in the production of photoporphyrin pigment in egg shells.
It was gratifying for me to organize and chair the symposium. The papers presented at the symposium are printed in the following pages. REFERENCES Morgan, T. H., A. H. Sturtevant, H. J. Muller, and C. B. Bridges, 1915. The mechanism of Mendelian heredity. Henry Holt & Co., New York, NY.
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on May 11, 2015
1 Presented at the 69th Annual Meeting of the Poultry Science Association as a part of a symposium entitled "Cytogenetics—Techniques, Research, and Practical Implications" sponsored by the Genetics section.
sium, "Cytogenetics—Techniques, Research, and Practical Implications" was organized. The objectives of this symposium were to review the avian cytogenetic research being done in the country and to understand how this branch of genetics could interface or complement other disciplines of poultry research. This was necessary because cytogenetic research involving domestic poultry has been escaping the attention of several poultry scientists. The four invited speakers are well recognized in the field and provided an overview of the importance of cytogenetic research. In the first paper, "Detection of Normal and Aberrant Chromosomes in Chicken Embryos and in Tumor Cells," S. E. Bloom of Cornell University reviewed the techniques for studying chromosomes and summarized his work on the frequency of chromosomal aberrations in various poultry populations and virus-induced tumor cells. His studies interfacing both cytogenetics and immunogenetics may pave a way in developing populations resistent to certain diseases, which the breeders are looking for. The second paper, entitled "Cytogenetic Studies of Embryos Developing Parthenogenetically in Turkeys" by Ko Harada and E. G. Buss of Pennsylvania State University, was presented by E. G. Buss. This paper included their most recent study on chromosome behavior in mosaic embryos of turkey and chickenturkey hybrids. N. S. Fechheimer of Ohio State University presented data on the frequency of chromosomal aberrations in chicken populations of commercial importance. In this third paper, "Origins of Heteroploidy in Chicken Embryos," he demonstrated the mode of origin of heteroploidy by using marker chromosome techniques. This work may arouse some interest in commercial breeders because of higher aberration rate in
1353
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on May 11, 2015
Since the development of cell theory, the most significant discovery in biology was the theory of chromosomal basis of hereditary by Morgan et al, (1915) by demonstrating a parallelism between abnormal genetic phenomenon and corresponding chromosomal aberrations. While the cytogenetic research advanced dramatically with various species, including humans, such work with poultry experienced a lag, primarily due to lack of proper techniques for identification and further characterization of the chromosomes as well as to the fact that aves have a rather large number of microchromosomes. Cytogenetic methods are useful not only for the routine identification of chromosomes and linkage relationships, but also for detection of pathological conditions in cells. Structural or numerical alterations in chromosome complement may be of use in sex-limited inheritance and increasing the genetic variation in a population. Interspecific transfer of genetic material, cell hybridization, polyploidization, and chromosome mediated gene transfer could offer practical advantages in commercial poultry production as we approach genetic plateaus. Karyological investigations also serve as a model for analysis of various etiological agents contributing to early embryonic mortality and developmental defects. As a part of total genetics program at the 69th annual meeting of the Poultry Science Association held at Purdue University a sympo-
1354
REDDY
broiler populations undergoing selection for broiler traits. In the final paper, "Marker Chromosomes and G-Banding for Location of Genes in the Chicken," R. N. Shoffner of the University of Minnesota provided the technique of combination of marker chromosome and G-banding differentiation in locating the blue egg gene and the gene involved in the production of photoporphyrin pigment in egg shells.
It was gratifying for me to organize and chair the symposium. The papers presented at the symposium are printed in the following pages. REFERENCES Morgan, T. H., A. H. Sturtevant, H. J. Muller, and C. B. Bridges, 1915. The mechanism of Mendelian heredity. Henry Holt & Co., New York, NY.
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on May 11, 2015