Download Branches of Genetics

Chapter 1 Introduction
Branches of Genetics
1. Transmission genetics
•
Classical or Mendelian genetics
2. Molecular genetics
– chromosomes, DNA, regulation of gene expression
– recombinant DNA, biotechnology, bioinformatics,
genomics, proteomics
3. Population, evolutionary genetics
•
•
•
allelic frequencies in populations
effects of migration
study relatedness of taxa via DNA and protein analysis
4. Quantitative genetics
–
effects of many genes
What is a gene?
•
•
•
•
•
•
•
•
A unit of inheritance
A specific location on a chromosome
A sequence of base pairs
Transcribed into mRNA
Encodes a protein
Expressed
The specifier of a phenotype
Composed of DNA
Model Organisms
cheap to grow
short generation time
can control mating
no ethical concerns
many offspring
some have simpler systems
small (most)
Why use model organisms?
•
•
•
•
Development
Disease
Metabolic pathways (biochemistry)
Evolution
• All living organisms share a common descent
Prokaryotic model organism
Bacteria
E. coli
Eukaryotic model organism
1. Unicellular
– Saccharomyces cerevisiae
• Bakers yeast
– Chlamydomonas reinhardtii
• Green algae
2. Multicellular
Neurospora crassa
– Orange bread mold
C. elegans
– Nematode worm
– 1mm long, 959 cells, transparent
Xenopus laevis
big eggs
http://www.biology.uiowa.edu/faculty_info.php?ID=1120
Zebra danio
transparent development
Arabidopsis thaliana
– small plant/mustard
family
Drosophila melanogaster
– Fruit fly
Mus musculus