AGB 121: Principles of Animal Genetics and Population Genetics (2+1)

PREPARATION OF METAPHASE SPREADS AND KARYOTYPING

• Cytogenetics is defined as the study of the morphology and behavior of chromosomes.
• Peripheral blood leucocyte culture technique is performed to obtain chromosomes at the metaphase stage of mitotic division. At this stage of cell division the exact 2n diploid number of chromosomes for any species (individual) can be visualized, photographed, counted and karyotypes can be prepared. Any change in the number or structure can be documented.
• Any alteration in the number or structure is referred to as numerical or structural chromosome abnormality.

  

• Karyotype: The chromosome constitution of a cell or an individual: Homologous pairs arranged in order of length and according to position of centromere.
• Idiogram: Idiogram is a term applied to any drawing of chromosomes as a karyotype to translate the interpretation of image, as of bands in a diagrammatic fashion.