Download genetics sylabus 4th semester

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FACULTY OF VETERINARY SCIENCE
DEPARTMENT OF PARACLINICAL VETERINARY STUDIES
ANIMAL HUSBANDRY SECTION
APPLIED GENETICS AND BIOSTATISTICS (AH2V02) COURSE OUTLINE
I. Genetics
Recommended Reading Materials:
Note: In full appreciation of the current cost of books in the country I am not by presentation
of this list making it a requirement for you to purchase these books. It would however enrich
you academically if you could consult these text for in-depth discussion of topics of personal
interest. The internet has a host of material on new genetic discoveries, genetic innovations
as well as debates and chat rooms on topical genetic issues. You are all strongly
encouraged to use all these sources of information to broaden your genetic horizons.
1. Peter J. Russel (1989) Genetics. 2nd Edition. Scott, Foresman and Company.
QH430.R87; ISBN 0-673-39843-9
2. Daniel L.Hartl and Andrew G.Clark (1989) Principles of population genetics. 2nd
Edition. Sinauer Associates, Inc. QH455.H37; ISBN 0-87893-302-6
3. Dale L Van Vleck, John E. Pollak and Branford E.A. Oltenacu (1987) Genetics for
Animal Sciences. W.H. Freeman and Company. QH432.V36; ISBN 0-7167-1800-6
4. Falconer D.S. (1989) Introduction to Quntitative Genetics. 3ed Edition. Longman
Scientific and Technical. ISBN 0-582-44195-1
Genetics course outline:
Part I
-Introduction and Basic principles
 Why study genetics in veterinary science?
 Cell division and Chromosome behaviour: Mitosis and Meiosis
 Roles of Mitosis and Meiosis
 Similarities and differences between mitosis and meiosis
 Chromosome numbers in some domestic species
PartII
-Mendelian genetics:
 Monohybrid crosses: Mendel’s first law
 Dihybrid crosses: Mendel’s second law, computating expected ratios
using the branch diagram or the product rule of probability approaches
 Trihybrid crosses:
 Crossing over, autosomal linkage and chromosomal genetic distances
 Gene interaction: Pleiotrophy and epistasis
Part III
-Sex chromosomes, sex linkage, sex determination and associated genetics

What are sex chromosomes?

Sex linkage genes: Definition in comparison to autosomal linkage,
classic examples of sex linked genes, detection in pedigrees

Sex determination:
Genotypic sex determination systems: X chromosome-autosome
balance system (Drosophila), Chromosomal sex determination
(Mammals, birds, butterflies/moths and bees)
Environmental sex determination: Crocodiles/alligators and in Bonellia

Sex-influenced traits and sex limited traits
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Part IV
-Multiple Alleles

Historical evidence of multiple alleles (Morgan’s 1912, Alfred Sturtevant
1913)

Multiple alleles in the human gene for ABO blood group series

Modification of Dominance relationships: Incomplete Dominance and
Codominance
Part V
-Elemen ts of population genetics




The Hardy-Weinberg (H-W) Law: Definition and assumptions
Determining whether a given population meets H-W expectations using
the 2 (Chi-square) goodness of fit test
Forces that change genotypic frequencies
Forces that change gene/allele frequencies
Part VI
-Elements of Quantitative genetics

What are quantitative traits?

The concept of variation and normal distribution

The classic model for quantitative traits: P=+A+D+E

Genetic parameters: Definition of heritability and repeatability

Methods of measuring/computing heritability and repeatability

Selection: Natural versus Artificial selection

What is artificial selection and what may be its objectives?

Artificial selection methods: Their advantages and limitations

Response to artificial selection: What is selection response? How is it
measured? What factors determine the rate of response to artificial
selection?
Part VI
-Relationships and Mating systems

Pedigrees and relationships using path coefficients

Inbreeding: Definition, computing inbreeding

Linebreeding, Outbreeding and Crossbreeding: Definitions and
Applications
-Major genes and application of molecular genetics in animal/veterinary science

Major genes in livestock: What are major genes? Why are they
important? Classic examples of major genes in animals.

Molecular genetics in animals: How has applied molecular genetics
benefited the animal/veterinary sciences? Examples of how applied
molecular genetics has benefited and is expected to benefit animal
sciences in future. Ethics with regards genetic manipulation. The
genetically modified organisms (GMO) controversy.
Part VII
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Practicals:
Practical Title
Number
1
Mitosis and meisosis
2
Mendelian genetics I
3
Mendelian genetics II
4
Mendelian genetics III
Sex linkage
6
Population Genetics
7
Quantitative Genetics
8
Relationships
Scheme of examination
Theory Paper
Continuous assessment
Viva
50%
30%
10%
Project
10%
Material to be covered during the practical
Students to solve mostly meiosis related
problems.
Students to solve problems on expected
genotypic and phenotypic ratios of dihybrid
and trihybrid crosses using the branch diagram
approach
Students to solve problems on expected
genotypic and phenotypic ratios of dihybrid
and trihybrid crosses using the product rule of
probability approach
Students to work on problems on partial linkage
and chromosomal genetic distances
Students to solve problems on the mode of
inheritance (autosomal/sex linked) and the
nature of the allele causing the observed
phenotype (dominant/recessive) given a
pedigree.
Students to solve problems on the Hardy
Weinberg equilibrium. Given a population, to
determine the probable force or forces causing
deviations from Hardy Weinberg expectations
Students to compute heritability and
repeatability estimates when presented with
different data
Students to work on converting pedigree
information into “arrow” diagrams. Students will
be required to figure out the relationship
coefficient between specific individuals in a
given pedigree.
Students will determine whether specific
individuals in a pedigree are inbreed or not, if
the former is true, to compute the inbreeding
coefficient.