iGenetics – Textbook Notes
-Genetics – the study of heredity
- Concerned primarily with the understanding that biological properties are transmitted
from parent to offspring
- Genetics includes heredity, molecular nature of the genetic material, the ways in which
genes control life functions, and the disruption and behaviour of genes in populations
Classical and Modern Genetics
- 1856-1863 - Gregor Mendel analyzed quantitatively the results of crossing pea plants
that varied in easily observable characteristics. After his death researchers realized that
Mendel had discovered fundamental principles of heredity (the foundation of modern
- 1972 – Paul Berg – constructed the first recombinant DNA molecule in vitro (work with
mutant genes so that they compare the differences with normal genes)
- 1973 – Herb Boyer, Stanley Cohen – first used a plasmid to clone DNA
- 1986 – Kary Mullis – developed the polymerase chain reaction (PCR) a technique for
amplification of selected DNA segments without cloning
Geneticists and Genetic Research
-Hypothetic-deductive method of investigation – consists of making observations,
forming hypotheses to explain the observation, making experimental predictions based
on hypotheses ad finally testing the predictions (for refinement purposes).
Subdisciplines of Genetics
1) Transmission genetics (aka classical genetics) – how genes and genetic traits are
transmitted from generation to generation and how genes recombine (exchange
between chromosomes). Analyzing the pattern of trait transmission in a human pedigree
or in crosses of experimental organisms is an example of transmission genetics study
2) Molecular genetics – deals with molecular structure and function of genes. Analyzing
the molecular events involved in the gene control of cell division, or the regulation of
expression of all the genes in the genome, are examples of molecular genetic studies.
Genetic analysis is a part of molecular genetics.
- Useful when studying neurobiology, cell biology, developmental biology, animal and plant
physiology, immunology and the structure and function of genomes.