Download Foundations of Human Development: Part 1, Heredity

PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Heredity
 Mechanisms of Heredity
Foundations of Human
Development
 Genetic Disorders
 Heredity is not destiny
Part 1: Heredity
Heredity
Mechanisms of Heredity
 Mechanisms of Heredity
 Genetic Material located in Chromosomes
 Chromosomes are made up of a Deoxyribonucleic acid
(DNA) Molecule
 Genetic Disorders
e ed ty is
s not
ot destiny
dest y
 Heredity
Chromosomes
Chromosomes--Four Key Points
 Four important points to
remember
1. Number of chromosomes in each cell
is important
 In humans there are 23 pairs
 46 chromosomes
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Chromosomes
Chromosomes--Four Key Points
1.
Number of chromosomes in each cell is important
2. Chromosomes are arranged in pairs
Return
Chromosomes
Chromosomes--Four Key Points
1.
Number of chromosomes in each cell is important
2.
Chromosomes are arranged in pairs
3. Pairs 1 to 22 are called
autosomes
 Pair 23 = sex chromosomes (X and
Y)
 Females (XX); males (XY)
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Chromosomes
Chromosomes--Four Key Points
1. Number of chromosomes in each cell is important
2. Chromosomes are arranged in pairs
3. Pairs 1 to 22 are called autosomes
4.Reproductive cells also called
g
gametes
 The sperm and the egg
 Only have 23 chromosomes
 Created through meiosis
 Crossover of genes
 Reduction into single chromosome
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Meiosis and Crossover
Crossover of Genes
 http://www.youtube.com/watch?NR=1&v=6xMX
KU7JnMQ&feature=endscreen
Genes and the Production of
Protein
Genes and the Production of
Protein
 Genes
 Genes
 Located at particular sites on
chromosome
Genes and the Production of
Protein
 Genes
 Located at particular sites on chromosome
 Located at particular sites on chromosome
 Contain directions for making
proteins
t i
DNA video
 http://www.youtube.com/watch?v=rromYAt1Lfw
&feature=related
 Contain directions for making proteins
 Made up of DNA
 DNA = Dioxyribonucleic acid
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Genes and the Production of
Protein
Detail of DNA Molecule
4 Bases
C t
Cytosene
Adenine
2 Base Pairs
Thymine
Cytosene
Guanine
Thymine
Adenine
Guanine
Principles and Processes of
Molecular Genetics
The transmission of traits: A
basic model
 The transmission of traits: A basic
model
 Multiple forms of gene present at
any gene’s position
 Alleles
 One from each parent
 If same, then homozygous
 If different, heterozygous
Transmission of traits:
A basic model

Transmission of traits:
A basic model
 Heterozygous Alleles
 3 possible outcomes
 Incomplete dominance
 Between the two extremes
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Incomplete Dominance
Transmission of traits:
A basic model
 Heterozygous Alleles
 3 possible outcomes
 Incomplete dominance
 Codominance
 Both characteristics expressed
http://flickr.com/photos/magnuscanis/355327700/
Codominance
Transmission of traits:
A basic model
 Heterozygous Alleles
 3 possible outcomes
 Incomplete dominance
 Codominance
 Dominance
 Dominant characteristic expressed
http://flickr.com/photos/dcruzin/12919997/
Dominance
Transmission of traits:
A basic model
 Exceptions to the rule
 Genes on the sex chromosomes
 X and Y Chomosomes
http://creativecommons.org/licenses/by-nc-nd/2.0/deed.en
Downloaded from:
http://www.genome.gov/glossary.cfm?key=sex%20chromosome
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Sex-Linked Disorders
Sex-linked Traits
 www.youtube.com/watch?v=H1HaR47Dqfw
Sex-Linked Disorders
Behavioural Genetics
 Examples
 Methods of studying Genetic
differences
 Hemophilia
 Red-Green Colour Blindness
 Adoption
p
studies
 Child similar to adoptive family =
Environment
 Child similar to biological family =
Genetics
Behavioural Genetics
Genetics of Twins
 Methods of studying individual
differences
 Adoption studies
 Twin studies
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Twin Studies--An Example
Twin Studies--An Example
 Is extroversion inherited?
 Take measure of extroversion
 Approaching stranger
 Find correlation between twins
 Monozygotic
 Dizygotic
Adoptive Studies-An Example
Behavioural Genetics
 Methods of studying individual
differences
 Adoption studies
 Twin studies
 Blended Families
Blended Families
Behavioural Genetics Results
Initiated by Reiss et al. (1994)
Sibling
Type
Full
% Genes share in
common
50%
Half
~25%
Step
0%
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Behavioural Genetics Results
Heredity
 Mechanisms of Heredity
 Genetic Disorders
 Heredity is not destiny
Genetic disorders
Sickle cell anemia
 Why do harmful alleles survive?
 If heterozygous, not harmful (maybe
even helpful)
 E.g., Sickle cell anemia
Heredity
Heredity is not destiny
 Mechanisms of Heredity
 Environment influences genetics
 Genetic Disorders
 Range of reaction
 Heredity
y is not destiny
y
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PSYC 2006: Foundations of Human Dev. Part 1: Heredity
September 19, 2013
Range of Reaction
Heredity is not destiny
 Genetics shape environment
 Niche picking
 Deliberately picking an environment
that will allow best development
according to genes
Heredity
 Conclusions
 Genetics provide important
framework for development
 Important to understand genetic link
 Environment also important
 Next: Prenatal Development and
Childbirth
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