behavioral genetics unit 1

_____ is the ultimate expression of the nervous system

behavior

behavioral genetics seeks for

understanding the genetic mechanisms that enable the nervous system to mediate appropriate behavioral stimuli

understanding the genetic architecture of a behavior requires

• which genes shapes behavior

• how do genes act together to shape behavioral phenotype

• the environment

• what extent do polymorphisms effect

behavioral output is influenced by both

development and physiology

what two things are external interactions that provide feedback info for behavior

• environmental interactions

• social interaction

behavior genetics spans into multiple fields such as

• experimental psychology

• ethology

• evolution

• genetics

• neuroscience

experimental psych in behavioral genetics

• Pavlov

• physiologist

• analyzed salivary secretions of his dogs in response to food presentation

• classical conditioning

ethology

• the study of animal behavior as a scientific discipline

• Karl von frisch, Konrad Lorenz, Nikolaus Tinbergen

• physiology

• discovered the organization and elicitation of individual and social behavioral patterns

• bee communication, imprinting, fixed action patterns

evolution and behavioral genetics

• Charles Darwin

• survival of the fittest

Mendelian inheritance

• gregor mendel - father of genetics

• discovered the basic principles of heredity

• wasn’t known until 30+ years after publication

classical genetics

• 1910s

• Thomas Hunt Morgan

• genes are located on chromosomes inside the nuclei of cells

neuroscience and behavioral genetics

• sir Bernard Katz

• elucidated the fundamentals of synpaisis - the junction across which nerve cells signal to each other

• action potentials

early approaches to the question of is there a heritable basis to behaviors

• artificial selection

• candidate gene approach - point mutations

earliest behavioral genetics experiments

R.C. Tyron 1942

• rats aertifically selected based on their ability to negotiate a maze

• poor preformers : dulls good pregeformers: bright

genotype by environment in R.C. Bryon

• dull rats could be improved. by rearing in an enriched environment

• bright rats were not better by enriched environment

• one of the first examples of genotype by environments

artificial selection and geotaxis

• artificially select based on movement towards or away from the gravitation force

• positively geotactic - high

• negatively geotactic - low

• jerry Hirsch

candidate gene approach

• Seymour benzer 1971

• identified fly mutants that have altered circadian rhythms

• all mutations mapped to the gene they called period

genetic model organisms

• fruit flies

• e coli

• rats/mice

• 
  

features of genetic model organisms

• short generation time

• production of numerous progeny

• the ability to carry out controlled genetic crosses

• the ability to be reared in a laboratory environment

• the a

approx. 77% of known human disease genes match a unique dna sequence in drosophila what are the models of disease and models of behavior

disease: huntingtons disease

alzhemiers

parkinsons disease

diabetes / obesity

cancer

aging

models of behavior: chemosensory function, sleep and activity. drug abuse

in Klamath et al - in c elegans silencing ___ with known human disease homologues generates phenotypes

334

genetic non-model systems include

• honeybees

• cavefish

• songbirds

challenges in the field of genetics