PSYC 458 Exam 4 Review

Nutrition transition

a way to conceptualize the changes from hunter-gatherer societies to modern times of obesity-related diseases and potential behavior change

Obesogenic

environments that facilitate obesity, in which low levels of physical activity are coupled with virtually unlimited access to energy-dense food

Complementation test

study design whereby parents that are heterozygous for the two mutations in question are mated together. If the two mutations represent different alleles of the same gene, some of the hybrid offspring should show the affected phenotype. However, if the mutations are in different genes, the wild-type alleles contributed by the parents would complement the mutant alleles so that the offspring would be heterozygous at both loci and therefore would not display the affected trait 

• e.g., ob mice are mated to db mice, phenotype being obesity

ob/ob mice vs db/db mice

• ob/ob mice -  mice that have a mutation in the gene that codes for Leptin (Leptin deficient), which results in obesity and decreased physical activity

• db/db mice - mice that have a mutation in the gene that codes for Leptin (overproduces Leptin), which results in obesity and greater insulin resistance

Anorexia nervosa

potentially fatal eating disorder characterized by severe food restriction, fear of gaining weight, and distorted body image

Eating disorders and estrogen

estrogen helps regulate appetite and satiety, lower levels of estrogen increase risk of binge eating

Endocannabinoid system and runners high

• Endocannabinoid system - the retrograde release of endocannabinoids (i.e., AEA and 2-AG) by postsynaptic neurons reduces the release of neurotransmitters from presynaptic neurons via CB1R activation

• Runners high - after episodes of intense aerobic exercise, such as long-distance running, some people report that they experience feelings of euphoria, relief from anxiety, and reduced ability to feel pain

Non-allelic recombination

form of genetic recombination occurring between misaligned, low-copy repeats

Oxytocin and social recognition

peptide hormone that plays a role in social behaviors

William’s Syndrome

disorder resulting from a deletion of 28 genes on chromosome 7 characterized by hyper-sociability, including decreased social anxiety

Turner syndrome

genetic condition in girls in which an X-chromosome monosomy (i.e., 45, X) where there’s only one complete X chromosome

Drosophila melanogaster courtship

1. The male orients his head towards the female 

2. The male taps the female's body with his forelegs

3. The male “sings” species-specific songs by vibrating his wing (either pulse song or sine song)

4. The male licks the females genitals 

5. The male mounts the female

Autism spectrum disorder (ASD)

characterized by persistent deficits in the ability to initiate and to sustain reciprocal social interaction and social communication, and by a range of restricted, repetitive, inflexible patterns of behavior, interests or activities that are clearly atypical or excessive for the individual's age and sociocultural context

Germline genetic engineering

the modification of genes in reproductive cells (sperm, eggs) using CRISPR Cas/9; controversial technology for eliminating genetic diseases

ClinVar

freely accessible public database of associations between genomic variation and aspects of human health

MAOA VNTR and criminality

“warrior gene” linked to reduced neurotransmitter breakdown, potentially increasing susceptibility to impulsive aggression and violent criminal behavior

DTC (direct to consumer) genotyping

service where people buy DNA tests directly from companies to get insight about ancestry, health risks, etc.

Precision medicine

an approach to treating a patient that takes into account their specific situation and their biology to tailor an individualized therapy, rather than to use an approach that works for most people, on average

SSRI and 5-HTTLPR

• SSRIs - most common medication treatment for depression 

• 5-HTTLPR - most common variant in the promoter region of the gene that codes for the serotonin transporter

CRISPR Cas/9

has been used to genetically engineer humans to have reduced risk of HIV infection

Weak genetic explanation

refers to the simple observation that genetic differences between people are statistically associated with individual differences in behavior

Strong genetic explanation

requires the identification and characterization of a specific genetic mechanism that accounts for the behavioral differences. Such an explanation necessarily involves biological components other than genes and can be considered causal

Herbert Spencer and Social Darwinism

• Herbert Spencer - introduced the term “survival of the fittest”; started the view of Social Darwinism 

• Social Darwinism - the view that providing support for the poor impedes the progression of evolution because with such charity the unfit survive and multiply, and without it they do not. It was only when these artificial supports are removed that natural selection can act to cull the unfit, which would lead to progress toward higher levels. Allowing the unfit to survive and multiply diminishes the overall fitness of the population and leads to its stagnation or degeneration 

Malthus on population growth and relief

• population growth - argued that population growth rates are exponential and, if unchecked, would outpace the rate of food production

• relief - argued that providing relief to the poor blocked the ultimate natural check on population growth

Francis Galton

• Coined the term eugenics 

• Eugenics - describe efforts to manage traits in human population by restricting or promoting reproduction

Kallikaks and involuntary sterilization

the Kallikak family were a cautionary tale used by Goddard to support eugenics, advocate segregation and forced sterilization of the “feebleminded”

Oliver Wendell Holmes, Jr.

Supreme Court Justice during Buck vs. Bell, in which it was decided that the Virginia Sterilization Act of 1924 did not violate the U.S. constitution; “Three generations of imbeciles are enough”

Carrie Buck

defendant in Buck vs. Bell; was sentenced to sterilization after giving birth (a result of rape)

Harry Laughlin

key figure in documenting and promoting compulsory sterilization laws; declared that “defective” individuals should not be able to reproduce (declared that 3 generations in Buck vs Bell were feebleminded); provided expert testimony for the Immigration Act of 1924, declaring that people from certain countries were likely to have mental defects and allowing them into the country would result in racial degeneration

IQ tests and immigration

IQ tests had been used to try and identify “mental defectives” to restrict them from immigrating to the U.S.

Influences on Nazi eugenic laws

Nazi Germany based some of its eugenic policies on US laws, but went further with mass genocide and breeding programs

Genetic essentialism

cognitive bias in which people consider genetic causes to be more important than other factors, and that traits influenced by genetic causes are unchangeable, fundamental, shared by all, and natural

Nuremberg Laws

made it illegal for anyone of “German or related blood” to marry or to have sexual intercourse with anyone from another group, including Jews, Gypsies, blacks, or their offspring

Thrifty gene hypothesis

posits combinations of genetic variants that were once favored by natural selection are now deleterious

Leptin

hormone secreted by fat that provides one of the many signals of satiety/hunger to the arcuate nucleus of the hypothalamus

Prader-Willi Syndrome

is a genetic disorder that typically produces obesity

Syndromic obesity

obesity that is a symptom of a disorder, such as in Prader-Willi syndrome

Affiliation…

has to do with engaging in positive social interactions with others

Attachment…

occurs when affiliation with a specific individual produces a social bond

Duplication on 7q11.23 (the same region of deletion in Williams syndrome) produces…

elevated social anxiety

Homologous recombination (i.e., crossing-over) occurs during meiosis, and generates…

genetic variation by exchanging DNA between chromosomes of paternal and maternal origin

Misalignment of recombination breakpoints can result in…

chromosomes containing unequal numbers of repeats where chromosomal material within and around the repeats is effectively deleted in one chromatid and inserted into the other