Genes and Behaviour 2022
Lecture 1
Introduction to Genes and Behaviour: a relationship between genes and behaviour?
Aim of the course: how genes influence the great variety of behaviours exhibited by
animals ranging from invertebrates to humans
Is there a genetic basis to behaviour and why does it matter?
The ugly history
19th century
eugenics = the study of or belief in the possibility of improving the qualities of the
humans species by the means of discouraging reproductions by persons having genetic
defects (negative eugenics) or encouraging reproduction by persons with inheritable
desirable traits (positive eugenics)
20th century: behavioural traits are in our blood, proclame superiority of an individuals
or group over others (racism, persecution and genocite)
Genetic determinism = “our fate is in our genes”
,For an informed debate on the subject of genetic determinism we need to first
understand how genes influence behaviour
● Ultimate (function, evolution)
● Proximate (mechanisms)
1. Fundamental biology: ultimate causation of behaviour
● What is the function of behaviour
=Behaviour represent the means by which animal interact with, and
adapt to their environment
● To increase chances of survival and reproduction
● Genetic factors and large environmental effects on behavioural plasticity
contribute to individuals variation in behavioural phenotypes
● Conclusion: one cannot understand the function, evolution, plasticity and
variability of behaviour without understanding its genetic basis
- Phylogenetic tree → common ancestor, can also trace behaviour through
phylogeny
- Like species killing each other → why
- Lethal violence denoted in the phylogenetic tree → biggest cluster
by the primates. Humans are ‘surrounded’ by species with lethal
violence
- Humans are pretty violence as well
2. Mechanestical: proximate causation of behaviour
● Classical model of how a behaviour is controlled
● Nervous system:
○ Sleepiness plus of smell of coffee → behaviour
○ Sensory input plus state gives decision and genetic variation and
gene expression is influenced
● Conclusion: Genes can influence mechanisms at any steps of the control
of a behaviour: sensing, state of behavioural decision
Thus two reason to approach the study of genes and behaviour, but conclusion;
genetics is the language of biology: by knowing what genes affect what behaviour we
can understand that behaviour evolved, but also the molecular and cellular basis of
behaviour
,What is a gene
● Made of DNA; Sequence of nucleotides
● Just know structure of a gene:
○ Promotor (arrow is site where RNA polwill bind)
○ Enhancer
○ Transcription factors
○ RNA polymerase
○ Introns and exons (Introns are spliced out → donor and receiver splice
sites exons form mRNA )
○ ORF (open reading frame) is only expressed, the rest (there are 5’ and 3’
untranslated regions of RNA)
○ Start and stop codon
○ 3’UTR?
○ poly A tail
● RNA one protein, multiple proteins can form one big protein
● Phenylalanine hydroxylase enzyme that influence behaviour → mutation; PKU
● Enhancers:
○ For gene regulation
○ Like gene evenstriped in drosophila
○ Enhancers lies around the gene (location is not important)→ can drive the
expression of the gene
○ One enhancer makes one stripe
■ Additive enhancers makes seven stripes in drosophila embryo
, Promotor: where, when and how much
Coding seq: what
Two types of genetic influences on human behaviour
1. Mendelian - mutation in a single gene
● Goes in families
● Are discontinuous; you have it or not
○ Not like weight that vary continuously
● Linked ot single genes - but big effect, some are carriers
- Phenotype
- PAH is a enzyme- when you miss the enzyme you have a disease
(genetics) but there is no disease with a proper diet
- Thus: phenotype is the appearance of an organism resulting from the
interactions of the genotype and the environment
Mutations
- A lot of mutations are found in a population → variation
- Can be deleterious or mutual (no effect)
- Insertion can cause frameshift and nonsense DNA
- SNP (single nucleotide polymorphism0 = variation in single nucleotide,
most neural, some affect coding or other processes
Lecture 1
Introduction to Genes and Behaviour: a relationship between genes and behaviour?
Aim of the course: how genes influence the great variety of behaviours exhibited by
animals ranging from invertebrates to humans
Is there a genetic basis to behaviour and why does it matter?
The ugly history
19th century
eugenics = the study of or belief in the possibility of improving the qualities of the
humans species by the means of discouraging reproductions by persons having genetic
defects (negative eugenics) or encouraging reproduction by persons with inheritable
desirable traits (positive eugenics)
20th century: behavioural traits are in our blood, proclame superiority of an individuals
or group over others (racism, persecution and genocite)
Genetic determinism = “our fate is in our genes”
,For an informed debate on the subject of genetic determinism we need to first
understand how genes influence behaviour
● Ultimate (function, evolution)
● Proximate (mechanisms)
1. Fundamental biology: ultimate causation of behaviour
● What is the function of behaviour
=Behaviour represent the means by which animal interact with, and
adapt to their environment
● To increase chances of survival and reproduction
● Genetic factors and large environmental effects on behavioural plasticity
contribute to individuals variation in behavioural phenotypes
● Conclusion: one cannot understand the function, evolution, plasticity and
variability of behaviour without understanding its genetic basis
- Phylogenetic tree → common ancestor, can also trace behaviour through
phylogeny
- Like species killing each other → why
- Lethal violence denoted in the phylogenetic tree → biggest cluster
by the primates. Humans are ‘surrounded’ by species with lethal
violence
- Humans are pretty violence as well
2. Mechanestical: proximate causation of behaviour
● Classical model of how a behaviour is controlled
● Nervous system:
○ Sleepiness plus of smell of coffee → behaviour
○ Sensory input plus state gives decision and genetic variation and
gene expression is influenced
● Conclusion: Genes can influence mechanisms at any steps of the control
of a behaviour: sensing, state of behavioural decision
Thus two reason to approach the study of genes and behaviour, but conclusion;
genetics is the language of biology: by knowing what genes affect what behaviour we
can understand that behaviour evolved, but also the molecular and cellular basis of
behaviour
,What is a gene
● Made of DNA; Sequence of nucleotides
● Just know structure of a gene:
○ Promotor (arrow is site where RNA polwill bind)
○ Enhancer
○ Transcription factors
○ RNA polymerase
○ Introns and exons (Introns are spliced out → donor and receiver splice
sites exons form mRNA )
○ ORF (open reading frame) is only expressed, the rest (there are 5’ and 3’
untranslated regions of RNA)
○ Start and stop codon
○ 3’UTR?
○ poly A tail
● RNA one protein, multiple proteins can form one big protein
● Phenylalanine hydroxylase enzyme that influence behaviour → mutation; PKU
● Enhancers:
○ For gene regulation
○ Like gene evenstriped in drosophila
○ Enhancers lies around the gene (location is not important)→ can drive the
expression of the gene
○ One enhancer makes one stripe
■ Additive enhancers makes seven stripes in drosophila embryo
, Promotor: where, when and how much
Coding seq: what
Two types of genetic influences on human behaviour
1. Mendelian - mutation in a single gene
● Goes in families
● Are discontinuous; you have it or not
○ Not like weight that vary continuously
● Linked ot single genes - but big effect, some are carriers
- Phenotype
- PAH is a enzyme- when you miss the enzyme you have a disease
(genetics) but there is no disease with a proper diet
- Thus: phenotype is the appearance of an organism resulting from the
interactions of the genotype and the environment
Mutations
- A lot of mutations are found in a population → variation
- Can be deleterious or mutual (no effect)
- Insertion can cause frameshift and nonsense DNA
- SNP (single nucleotide polymorphism0 = variation in single nucleotide,
most neural, some affect coding or other processes
