Genetics

Question 1

Why study genetics?

Answer 1

Svartberg and Forkman (2002) support harmonious dog-human partnership
Gazit & Terkel (2003) enhancing abilities of service dogs important for human health
improve welfare
resolve behavioural problems
production traits

Question 2

Identifying a genetic component

Answer 2

Indirect- sex/breed differences

Direct- calculation of h2

Question 3

Svartberg (2006)

Answer 3

show dogs bred for looks increase in aggressiveness

Question 4

McCune (1995)

Answer 4

paternity influences kitten friendliness- friendly fathers produce friendly kittens even when controlled for environment

Question 5

Important behaviours for cattle

Answer 5

reaction to confinement
temperament (safety, handling efficiency)
milking temperament
feeding behaviours
exit from holding area
selected for calmness

Question 6

Scott & Fuller (1965) single gene

Answer 6

barking and struggling demonstrated simple dominant allels in basenji and cocker spaniel

Question 7

Ilska et al (2017)

Answer 7

h2 of behaviours in labradors all very low

Question 8

TH gene

Answer 8

close to SNP associated with aggression

TH linked to activity and inattention

Question 9

Llinamo et al (2007) h2 in dogs for aggression

Answer 9

human- 0.77
dog- 0.81
correlation between these was 0.4
however they used similar litters and kept in similar environments

Question 10

Staiger et al (2016) horses

Answer 10

anxious, tractable, agnostic, excitable explained 64% of trait variance- strong genetic component

Question 11

Mills & Redgate horses

Answer 11

predisposition for crib biting, weaving and stall walking

Question 12

D’Earth et al (2010)

Answer 12

low h2 for lots of behaviours

Question 13

If not one gene then how?

Answer 13

linkage
modern gene tech
knock out studies
GWAS
QTL

Question 14

Coat colour in cats

Answer 14

black= amicable
orange= aggressive
red/cream/tortoiseshell= less dosile
colour pigments produced by same chemical pathways as some NTs
Wilhelmy et al (2016) found No relationship

Question 15

Jacobs et al (2016) horses

Answer 15

coat colour may impact behaviour

black mares more self reliant

Question 16

Bovine neuroreceptor 5 gene (NYPSR)

Answer 16

linked to appetite and feeding

Question 17

Melanocortin 4 receptor gene (MC4R)

Answer 17

food intake capacity

Question 18

Epigenetics

Answer 18

DNA methylation changes activity without changing sequence
reversible
therapeutic applications
EG rats licking pups- silencing epigenetic makers on glucocorticoid receptors
licking removes silencing marker thus turns on and enhances future stress coping

Question 19

Dovc et al (2009) developed a cattle database of gene and genetic markers for milk production

Answer 19

contains 943 genes and genetic markers involved in mammary gland development
44 genes found by multiple independent analysese were suggested as most promising candidates

Question 20

Sun et al (2013) 14 new genes for meat quality in chicken using GWAS

Answer 20

included genes linked to meat colour brightness and intramuscular fat content in breast muscle

Question 21

The NHGRI dog genome project

Answer 21

Ostrander’s lab at NIH
Working to find DNA variants associated with disease and reduce their occurence
Suggest since dieases are similar to those of humans likely to provide insight into human research as well

Question 22

Pritchard et al (1994) physiological influence on benefits of exercise in dogs

Answer 22

• Exercise can provide stimulus for increased production of endothelium relaxing factor (EDRF) and nitric oxide mediated epicardial coronary artery dilation
• Contributing to beneficial effects of exercise on the cardiovascular system
• Gene associated with this is ECNOS and they found mRNA levels for ECNOS significantly higher in exercised dogs

Question 23

Corbet & Burrow (2000) beef cattle

Answer 23

found low h2 for slight speed in zebu-derived beef cattle

Question 24

Lim et al (2004) showed enhancing

Answer 24

gene for vassopressin V1a receptor (V1aR) enhances partner preference formation in meadow vole
Although not companion animals, they show that change in expression of a single gene can profoundly alter social behaviour

Question 25

Ronai et al (2017) linked DRD4 gene to activity-impulsivity in dogs

Answer 25

police german shepherd with at least one 2a allele showed signif. higher scores on A-I dimension of dog ADHD rating scale

Question 26

Campbell & Marchant (2018) use of chemogenetics in behavioural neuroscience

Answer 26

• Increase in neuroscience technologies allows precise manipulation of neural circuits in awake, behaving animals- can look at the way neural circuit influence behaviour
• Chemogenetics= allows for reversible remote control of specific cell pops/neural circuitry by injection/ micro-infusion

Question 27

Craft et al (2018)

Answer 27

integration of contact networks and genomic approaches useful
Allows answering complicated Qs about animal behaviour and pathogen transmission

Question 28

Thompson et al (2017) epigenetic ageing clock in dogs

Answer 28

• DNA methylation represents a form of genome modification that regulates gene expression
• Assessed blood DNA methylations and found age related DNA methylation changes in canids similar to that of humans
• Suggesting this epigenetic mechanism associated with age is an evolutionary conserved mechanism