Lecture 1 - Cognitive Genetics Flashcards
Explain with two different genes.
Genetic variation -> Protein -> Brain -> Cognition
Two different genes. Different protein structures. Might lead to differences in brain structure. Differences in brain development (e.g. memory).
Cognitive genetics.
Concerned with linking genetic variation to variation in a cognitive ability. Measure gene, measure cognition, then correlate.
Complex trait.
A quantifiable property of an organism influenced by multiple genetic and environmental factors as well as interactions between them.
Why is cognitive ability considered a complex trait?
There are maybe hundreds/thousands of genes leading to a single trait.
- To date, the findings that have reached genome-wide significance for a confirmed association with ADHD are…
A. Extremely supportive
B. Somewhat supportive, but many need replication
C. Only suggestive and must be replicated
D. Not suggestive, not helpful, and a waste of time
C. Only suggestive and must be replicated
Genome-wide association studies
A. investigates variation in genes across the entire genome
B. investigates how these genes influences individual differences in specific cognitive process
C. Take all genes and correlate with behaviour
D. Doesn’t matter what hypothesis, not biased
E. Need at least 40 000 ppl, and precision in collecting data is sacrificed
All
- Davis, Haworth and Plomin (2012) conducted a study where different childhood outcomes (?) of 6759 twin pairs were geocoded to their postcode in England or Wales.
It was found that the amount to which genes predicted ADHD varied depending on proximity to London. What kind of influences would be contributing this variation?
A. Additive genetic influences
B. Shared environmental influences
C. Non-shared environmental influences
D. Single nucleotide polymorphism
C. Non-shared environmental influences
3. What kind of study would be conducted if you wanted to look at how a specific gene influences individual differences for a cognitive process? A. Twin studies B. Candidate gene studies C. Genome wide association studies D. Heritability studies
B. Candidate gene studies
4. What term describes the physical appearance of an organism with respect to a trait? A. Intermediate phenotype B. Complex trait C. Endophenotype D. Phenotype
D. Phenotype
5. In the studies mentioned of the Dopamine Transporter gene (DAT1) (Bellgrove et al. (2005) and Loo et al. (2003)) which type of repeat allele does not sustain the best attention in sustained attention tasks? A. 9/9 B. 9/10 C. 10/10 D. They all do equally badly
C. 10/10
Participants with one copy of the 9-repeat allele (9/9 or 9/10) have higher dopamine transport density compared to 10/10 carriers
- ____________ reflect a change in a single base in the DNA that differs from the usual base at that position and ___________ indicates Polymorphism in the length of tandemly repeated short sequences of DNA.
- Single nucleotide polymorphism (SNP)
2. variable number of tandem repeats (VNTR)
7. If attention ability is highly correlated within both MZ and DZ pairs then the effect must be due to A. Genetics B. Non-shared environmental effects C. The environment D. Polymorphism
C. The environment
- Children with ADHD who have the 7-repeat allele display ________, where as those without the 7-repeat allele are at risk for poorer cognition.
A. Extreme behaviour but no cognitive symptoms
B. Cognitive symptom and no extreme behaviour
C. Mild behaviour but no cognitive symptoms
D. Mild behaviour and cognitive symptoms
A. extreme behaviour but no cognitive symptoms.
Bellgrove & Swanston - ADHD, 7 repeat allele made fewer errors in sustained attention task
- What is the most commonly studied variant in the Dopamine Transporter Gene (DAT1)?
A. VNTR in the 5’UTR
B. VNTR in the 3’UTR
C. SNP in the 3’UTR
D. SNP in the 2’UTR
B. VNTR in the 3’UTR
- What is (are) the strength(s) of the Genome-wide association study?
A. No prior information about the gene is required.
B. Allows examination of genetic variation across the genome.
C. Allows specific hypothesis to be tested.
D. Both A and B.
D. Both A and B.
11. How can genetic information help? A. Improved diagnosis B. Improved treatment Pharmacology C. Development of environmental interventions D. Improved treatment Behavioural E. All of the above
E. All of the above
- What is an example of an endophenotype identified for ADHD?
A. hyperactivity
B. sustained attention
C. Dopamine Transporter gene
D. none of the above
B. sustained attention
- If attention ability is highly correlated in monozygotic but not dizygotic twins then the effect must be due to ____?
A. genetics
B. environment
C. non-shared environmental effects
D. all of the above
A. genetics
In twin studies, any differences in attention ability if twins share genes and environment, must be due to
A. genetics
B. environment
C. non-shared environmental effects
D. all of the above
C. non-shared environmental effects
- What is a likely explanation for the results of Davis et al’s twin study?
A. ADHD can be explained by genes alone
B. ADHD can be explained by the interaction between genes and non-shared environment
C. ADHD can be explained by the interaction between genes and shared environment
D. none of the above
B. ADHD can be explained by the interaction between genes and non-shared environment
- What does a candidate gene study look at?
A. the effect of multiple genes on a specific cognitive process
B. the effect of a specific gene on multiple cognitive processes
C. the effect of a specific gene on a specific cognitive process
D. the entire genome and any cognitive processes
C. the effect of a specific gene on a specific cognitive process
- What is genome wide association best at identifying?
A. rare variants of a small effect
B. high effect, common variants
C. low frequency variants with intermediate effects
D. common variants implicated in common disorders
D. common variants implicated in common disorders
- What is a weakness of a genome wide association study?
A. does not tell you which genes are responsible
B. not all possible genes are investigated
C. very large sample sizes needed
D. prior information about gene needed
C. very large sample sizes needed
- If attention ability is highly correlated within both monozygotic and dizygotic pairs, is the effect likely due to genetics or environment?
A. Environment
B. Genetics
C. Both A and B
D. Impossible to tell
A. Environment
- What is a complex trait?
A. A quantifiable property of an organism influenced by multiple genetic factors.
B. A property of an organism that cannot be detected directly.
C. A quantifiable property of an organism influenced by multiple environmental factors.
D. A quantifiable property of an organism influenced by multiple genetic and environmental factors as well as interactions between them.
D. A quantifiable property of an organism influenced by multiple genetic and environmental factors as well as interactions between them.
- What methods are there to decide how a gene is related to a behaviour?
A. Twin and heritability studies only.
B. Twin and heritability studies, candidate gene studies, and genome-wide association studies.
C. Candidate gene studies and genome-wide studies only.
D. Genome-wide associate studies only.
B. Twin and heritability studies, candidate gene studies, and genome-wide association studies.
- Which of the following is NOT a common type of genetic variation?
A. Single nucleotide polymorphism.
B. Variable number of tandem repeats.
C. Triple nucleotide polymorphism.
D. None of these are common types of genetic variation.
C. Triple nucleotide polymorphism.
- What findings have been described in the literature for DRD4?
A. Children with ADHD with the 7-repeat allele made fewer errors on a sustained attention task than those without the allele.
B. Children with ADHD with the 7-repeat allele made more errors on a sustained attention task than those without the allele.
C. Children with ADHD who have the 7-repeat allele display extreme behaviour but no cognitive symptoms whereas those without the 7-repeat allele are at risk for poorer cognition.
D. All of the above.
D. All of the above.
- Is it possible to determine which genes are involved in cognitive variation using the twin studies method?
A. Yes.
B. No.
C. It depends on the type of cognitive variation being studied.
D. Impossible to tell.
D. Impossible to tell.
Tells us genes are important but not which gene.
twin studies allow estimation of genetic and environmental contributions
- Explain the difference between genome wide-association studies and candidate gene studies?
A. Genome-wide studies measure the entire genome but do not infer the specific causal genes for a disorder. Whereas, candidate gene-studies map only the variability of a few genes allowing a more specific indication of the effects of a few particular genes.
B. Genome-wide studies are an expensive way of mapping the genome and infer specific causal genes. Candidate gene studies study only a few genes within the genome and show the direct link between the disorder and its genetic basis
C. Both genome-wide studies and candidate gene studies produce similar data and only differ in overall cost
D. All of the above
D. All of the above
Not really sure
- Which of these is not a way to measure genetic and cognitive variability?
A. Twin studies
B. Genome-wide associations
C. Brain-activation mapping
D. Candidate gene
C. Brain-activation mapping
- Explain the differences between a phenotype and an endophenotype
A. There is no difference
B. A phenotype measures the physical appearance of an organism with respect to a trait, whereas, an endophenotype measures a component along the causal pathways between the distal genome and the disorder
C. An endophenotype measures the physical appearance of an organism with respect to a trait, whereas, an phenotype measures a component along the causal pathways between the distal genome and the disorder
D. One exists only theoretically
B. A phenotype measures the physical appearance of an organism with respect to a trait, whereas, an endophenotype measures a component along the causal pathways between the distal genome and the disorder
- What is a disadvantage of candidate gene studies?
A. It is very expensive
B. A specific hypothesis and prior knowledge is needed before conducting one
C. Many participants are needed to gain information
D. It measures the interaction between genes and the environment
B. A specific hypothesis and prior knowledge is needed before conducting one
- What is an example of an endophenotype for ADHD?
A. Single nucleotide polymorphism
B. Variable number of tandem repeats
C. Sustained attention
D. ADD
C. Sustained attention
- What is not an application of the genetic study of ADHD?
A. Improved treatments
B. Improved diagnosis
C. Environmental Interventions
D. Drug-based Behaviour modification
D. Drug-based Behaviour modification
