Bio: Genetics Flashcards
Genes
The working sub-units of DNA which are passed from parent to child through inheritance.
Traits
Genes are inherited and lead to biological traits which can then lead to behaviors. There is not an ‘aggression gene’ that is inherited but a gene may lead to the biological trait of a lack of MAOA which can influence the expression of aggressive behavior.
Genome
Genome is the complete set of genetic information for an organism. The human genome is spread across 23 chromosomes, which hold our DNA, or genetic code.
Phenome
All the phenotypes of an organism. The phenotypes are the physical and behavioral traits. The phoneme is what is most influenced by the environment.
Monozygotic (MZ)
The clinical term for identical twins; they share 100% of their DNA.
Dizygotic (DZ)
The clinical term for fraternal twins; this occurs when two fertilized eggs are implanted in the uterus wall at the same time. When two eggs are independently fertilized by two different sperm cells, fraternal twins result. The genetic similarity is the same as any other siblings.
Concordance Rate
The probability that a pair of individuals will both have a certain characteristic, given that one of the pair has the characteristic. In the case of twin studies, it is the probability that if one twin has a trait, that the other will also have that trait.
Meta-analysis
Looking at the statistical results of many other studies done on a similar topic in order to draw conclusions.
Prospective Study
A study when participants are chosen based on a specific variable and then are monitored over time to see what behavior develops.
Linkage Study
When a researcher looks for a trait that appears frequently in an extended family and then works backward to look for genetic similarities.
Diathesis-Stress Model
The theory that you may have genes that may make you more likely to have certain traits if those genes are exposed to the appropriate environmental stressors.
Genetic Markers
Researchers examine the DNA for polymorphism – (the presence of genetic variation.) These polymorphisms are referred to as genetic markers.
Genome Wide Association Studies (GWAS)
An examination of a genome-wide set of genetic variants in a large sample of individuals to see if any variant is associated with a trait.
Epigenetics
A field of study which suggests that genes don’t ‘cause’ behavior. Instead, genes must be ‘expressed’. The expression of a gene is a complex chemical reaction to environmental or physiological change.
Methylation
A process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. Methylation can help determine which genes are expressed and which are not.
