Isyllabus Icalendar Iadvice Igenetics intro Igenetics & the organism LECTURE 01: INTRODUCTION
SYLLABUS
Web Page: SYLLABUS
Electures Equizzes Eproblems Etutorials Eexams SYLLABUS
CALENDAR
GRADES
Echeating, plagiarism & academic dishonesty Ereligious holidays – notify me by Monday, September 1 st Eillness & family emergency SYLLABUS
$core course in biology $essential aspect of all biology courses $importance for professional schools $learn vocabulary but... $logic & analyses > memorization & regurgitation $problem-based course, practice $recommend Schaum’s Outline: Genetics $assigned problems tutorial presentations $don’t understand something? INFORMATION & ADVICE ASK
LEARNING SPACED TRAINING ~ study every night MASSED TRAINING ~ cramming MEMORY TIME STUDY HABITS
6 PhDs Roberts Andres $ 750 K
LECTURE 01: GENETICS & THE ORGANISM FCH1 key concepts Fvariation Fquantitative methods Fclassical methods Fcomplications
Habout: transmission, location, structure, function & variation in genetic material H not about: human genetics, biotechnology, molecular biology (but some) Hgenetic material does 3 things: 1.copy 2.code 3.change GENERAL INTRODUCTION
SECTION 1: TRANSMISSION Fpatterns of transmission Fcellular events during meiosis Fcombined for chromosome theory of inheritance (proof published in Genetics 1(1) & 1(2), 1916)
CHAPTER 1: KEY CONCEPTS (that you should already know) FDNA = hereditary material FDNA = double helix of 2 wound chains oriented in opposite directions FDNA is copied – chains separate and serve as templates 2 identical daughter DNA molecules Fgenes = functional units of DNA*
Fgene = segment DNA sequence transcribed RNA FRNA is translated amino acid sequence of protein Fprotein = main determinants of structural and physiological properties of organisms Fspecies characteristics encoded by genes FP = G + E + G*E Fgenetic variation from changed forms of genes CHAPTER 1: KEY CONCEPTS (that you should already know)
PHENOTYPIC VARIATION Fcharacters vary in nature FWHY is an evolutionary or ultimate question FHOW is a mechanistic or proximate question Fconcept of inheritance from ancient breeders FGalton: blended characteristics, quantitative phenotypes, measure individuals, continuous variation FMendel: particulate inheritance, qualitative phenotypes, counting individuals, discontinuous variation Fboth concepts of heredity have same physical basis Fdiffer in how they are studied only
P = G + E + G*E phenotype = genotype + environment + interaction PHENOTYPIC VARIATION
G 1 G 2 PHENOTYPE G ENVIRONMENT E 1 E 2 E 1 E 2 G+E E E 1 E 2 E 1 E 2 G*E NORMS OF REACTION
P = G + E + G*E phenotype = genotype + environment + interaction PHENOTYPIC VARIATION where does the E come from ?
GENES MESSAGES PEPTIDES PROTEINS PROTEIN COMPLEXES ORGANELLES NEURONS ASSEMBLIES STRUCTURES CIRCUITS NERVOUS SYSTEM WHOLE ANIMAL BEHAVIOR EXPERIENCE ENVIRONMENT PLASTICITY ENVIRONMENT PHENOTYPIC VARIATION
P = G + E + G*E phenotype = genotype + environment + interaction PHENOTYPIC VARIATION where does the G come from ?
GENETIC COMPONENT Fgenetic variation from alleles = different forms of genes Fcauses polymorphism = multiple phenotypes Fcaused by mutation = change in DNA sequence (natural or induced) Fmutants – many types, very low frequency initially Fterms: gene, allele, locus Fmore terms: wild type, mutant, mutation, mutant allele
GENES MESSAGES PEPTIDES PROTEINS PROTEIN COMPLEXES ORGANELLES NEURONS ASSEMBLIES STRUCTURES CIRCUITS NERVOUS SYSTEM WHOLE ANIMAL BEHAVIOR EXPERIENCE ENVIRONMENT PLASTICITY PHENOTYPIC VARIATION
GENES MESSAGES PEPTIDES PROTEINS PROTEIN COMPLEXES ORGANELLES NEURONS ASSEMBLIES STRUCTURES CIRCUITS NERVOUS SYSTEM WHOLE ANIMAL BEHAVIOR EXPERIENCE ENVIRONMENT PLASTICITY PHENOTYPIC VARIATION
0 1 FREQUENCY PHENOTYPE 1 gene 1 allele ( = 0) GENETIC COMPONENT
FREQUENCY PHENOTYPE 1 gene 2 alleles GENETIC COMPONENT
FREQUENCY PHENOTYPE 2 genes 2 alleles GENETIC COMPONENT
FREQUENCY PHENOTYPE genes 14n14n 2 alleles GENETIC COMPONENT
FREQUENCY PHENOTYPE many genes many alleles GENETIC COMPONENT
H natural sources: H gene # / influence from F 2 phenotype ratios H artificial selection GENETIC COMPONENT
QUANTITATIVE METHODS Fis there a genetic component for a trait of interest? Fcan you do artificial selection experiments? – a response indicates genetic components F rate of response indicates number of genes Fwhat types of organisms can be used?
xxxx FREQUENCY 0.00 PHENOTYPE GENETIC COMPONENT
relax selection fixed not GENETIC COMPONENT
H induced sources (... stay tuned!): H chemical mutagens – “point” mutations H ionizing radiation – chromosome rearrangements H transposon insertions – disrupt gene activity H transgene expression– block / add / change gene function – qualitative / quantitative – spatial / temporal control H natural sources: H gene # / influence from F 2 phenotype ratios H artificial selection GENETIC COMPONENT
CLASSICAL METHODS F isolate or select mutants for process of interest F design of experiment important Fcharacterize genetic change – controlled matings or crosses Fterms: dominant, recessive Fmapping: recombination, physical, insitu hybridization Fmolecular biology: cloning, sequencing, rescue Ffunctional studies: mosaic, complementation, biochemistry, anatomy
UNIFIED METHODS (Quantitative + Classical) Fgenomics Fproteomics
P = G + E + G*E phenotype = genotype + environment + interaction PHENOTYPIC VARIATION where does the G*E come from ?
E1E1 E2E2 G1G1 G2G2 INTERACTION COMPONENT
G 1 G 2 PHENOTYPE G ENVIRONMENT E 1 E 2 E 1 E 2 G+E E E 1 E 2 E 1 E 2 G*E NORMS OF REACTION
COMPLICATIONS Fexpressivity: strength of phenotype in individuals Fpenetrance: number of individuals of given genotype expressing phenotype Fpolygeny: >1 gene/phenotype Fpleiotropy: >1 phenotype/genotype
POLYGENY GENE GENE PHENOTYPE GENE BIOCHEMICAL PATHWAY: PHENOTYPE COMPETITION / INHIBITION: PHENOTYPE ENZYME CATALYSIS: PHENOTYPE
PLEIOTROPY PHENOTYPE GENE PHENOTYPE PHENOTYPE BIOCHEMICAL PATHWAY:GENE RELATED PHENOTYPES:GENE UNRELATED PHENOTYPES:GENE
1 GENE
POLYGENY
PLEIOTROPY
H phenotype H significance H interesting H invariant WHAT IS A GOOD MODEL ORGANISM ? H convenience H cost H sample size H maintenance H disease H research tools H genetics / genomics H molecular biology H cell biology H pharmacology H physiology H anatomy H ethical issues H organisms H research questions H homology ?