A.2 Principles of Genetics
Overall Progress
Overall Progress
Genetics, the study of heredity and variation in living organisms, has a rich history spanning centuries. From early observations of inherited traits to the discovery of DNA's structure and the completion of the Human Genome Project, the field has undergone remarkable transformations, revolutionizing our understanding of life itself [Griffiths et al., 2000].
Mendel published his work on pea plants, establishing the fundamental laws of inheritance. His concepts of dominant and recessive traits laid the foundation for modern genetics [Mendel, 1865].
Friedrich Miescher isolated "nuclein" (later known as DNA) from white blood cells, marking the first isolation of DNA [Dahm, 2008].
James Watson and Francis Crick proposed the double-helix structure of DNA, based on X-ray crystallography data from Rosalind Franklin and Maurice Wilkins [Watson & Crick, 1953].
Frederick Sanger developed the chain-termination method for sequencing DNA, revolutionizing genomic research [Sanger et al., 1977].
The Human Genome Project, an international scientific research project aimed at determining the sequence of the human genome and identifying and mapping all human genes, was completed [Collins et al., 2003].
DNA (Deoxyribonucleic Acid) is a molecule composed of two chains that coil around each other to form a double helix. The information in DNA is stored as a code made up of four chemical bases: adenine (A), guanine (G), cytosine (C), and thymine (T). The order of these bases determines the information available for building and maintaining an organism [Watson & Crick, 1953].
These base pairing rules are crucial for DNA replication and transcription processes. The complementary nature of base pairs allows for the accurate transmission of genetic information [Alberts et al., 2002].
Click the "Add Base Pair" button to simulate the addition of random base pairs to a DNA molecule. Observe how the proportions of each base change as more pairs are added.
Total base pairs: 0
Gregor Mendel's work with pea plants led to the foundation of modern genetics. His experiments revealed several fundamental principles of inheritance [Mendel, 1865]:
These laws can be expressed mathematically. For example, in a monohybrid cross between two heterozygous individuals (Aa × Aa), the probability of offspring genotypes follows the ratio:
P(AA) : P(Aa) : P(aa) = 1/4 : 1/2 : 1/4
Where:
The Central Dogma, first stated by Francis Crick in 1958, describes the flow of genetic information within a biological system. It can be summarized as "DNA makes RNA makes protein" [Crick, 1970].
The rate of protein synthesis can be described by the following equation:
dP/dt = ks * [mRNA] - kd * [P]
Where:
The history of genetics is a testament to human curiosity and scientific progress. From Mendel's pea plants to the completion of the Human Genome Project, our understanding of heredity and the molecular basis of life has grown exponentially. As we continue to unravel the complexities of genetics, new technologies like CRISPR gene editing and personalized medicine promise to revolutionize healthcare and our relationship with the genome [Doudna & Charpentier, 2014].
The field of genetics continues to evolve, with ongoing research in areas such as epigenetics, gene therapy, and synthetic biology. These advancements not only deepen our understanding of life but also raise important ethical questions about the manipulation of genetic material [Baltimore et al., 2015].
by Khan Academy • Multiple videos, each 10-15 minutes
A comprehensive series of video lessons covering the basics of genetics.
by CrashCourse • 12:59
An engaging video explaining DNA structure and replication.
Griffiths, A.J.F., Wessler, S.R., Carroll, S.B., and Doebley, J. (2015) . W. H. Freeman.
A comprehensive textbook covering the fundamentals of genetics.
Key topics: Mendelian genetics, DNA structure and function, Gene expression, Genetic analysis techniques
Mukherjee, S. (2016) . Scribner.
A narrative history of genetics, from Mendel to modern gene editing.
Key topics: History of genetics, Key discoveries in genetics, Ethical implications of genetic research
An interactive primer on genetics and the history of genetic discoveries.
Type: Interactive Learning Module
Interactive tutorials and virtual labs on various genetics topics.
Type: Educational Website with Interactive Elements
A game exploring Mendelian inheritance patterns.
An interactive game demonstrating the processes of transcription and translation.
A podcast from the Genetics Society, exploring the world of genes, genomes, and DNA.
A comprehensive introduction to biology, including genetics topics.
Provider: MIT OpenCourseWare
A tool for visualizing genetic sequences and annotations.
Type: Web-based Visualization Tool
NIH genetic sequence database, an annotated collection of all publicly available DNA sequences.
Type: Genetic Sequence Database
Watson, J.D. and Crick, F.H.C. (1953) . Nature.
The landmark paper describing the double helix structure of DNA.
Mendel, G. (1865) . Verhandlungen des naturforschenden Vereines in Brünn.
Mendel's original paper describing his experiments with pea plants and the laws of inheritance.