- Are twin studies reliable?
- Why is it important to genetic researchers to study twins?
- What are the disadvantages of twin studies?
- Who carries the twin gene?
- Can you have twins if it doesn’t run in family?
- Why are identical twins useful for studying variation?
- Do twins have the same fingerprints?
- Are twins DNA different?
- What types of questions would twin studies not be as helpful?
- Is personality more nature or nurture twin studies?
- Why are twins different heights?
- What is Twin method?
- Do twins come from Mom or Dad?
- What are identical twins called?
- What is concordance rates in twins?
- Why are twin studies useful?
- Why are twin studies flawed?
- How do twin studies help establish heritability?
- Why dont identical twins look exactly the same?
- How does the environment affect identical twins?
- Can someone who is a twin have twins?
Are twin studies reliable?
Both studies confirm that greater similarity of treatment does not make MZ twins are more similar.
Separated twin studies and standard twin studies give very similar results.
Critics are quick to point out that many twins in separated twin studies were not totally separated..
Why is it important to genetic researchers to study twins?
We study twins to understand how much of the difference in a trait between people is caused by genes and how much is caused by the environment. These studies are important because they help scientists quantify genetic and modifiable environmental factors that increase the risk of certain diseases.
What are the disadvantages of twin studies?
Limitations of twin studies Results from twin studies cannot be directly generalized to the general population, due to lack of randomization; in addition, they are different with regard to their developmental environment, as two fetuses growing simultaneously.
Who carries the twin gene?
This is why fraternal twins run in families. However, only women ovulate. So, the mother’s genes control this and the fathers don’t. This is why having a background of twins in the family matters only if it is on the mother’s side.
Can you have twins if it doesn’t run in family?
You may have heard that twins “run in families.” This is partially true. Your chances of having fraternal twins may be higher if you’re a fraternal twin yourself or if fraternal twins run in your family.
Why are identical twins useful for studying variation?
Twins are a valuable source for observation because they allow the study of environmental influence and varying genetic makeup: “identical” or monozygotic (MZ) twins share essentially 100% of their genes, which means that most differences between the twins (such as height, susceptibility to boredom, intelligence, …
Do twins have the same fingerprints?
The bottom line But, like those who aren’t twins, identical twins all have unique fingerprints. Due to environmental factors that affect their development inside the womb, it’s impossible for identical twins to have the exact same fingerprints.
Are twins DNA different?
Because of recombination, siblings only share about 50 percent of the same DNA, on average, Dennis says. So while biological siblings have the same family tree, their genetic code might be different in at least one of the areas looked at in a given test. That’s true even for fraternal twins.
What types of questions would twin studies not be as helpful?
Some of the questions that can be answered about human development with twin studies are: o Questions about personality, behavior, attitude and physical traits. Some questions that wouldn’t be as helpful are: o Nature vs Nurture because there are different type of twins.
Is personality more nature or nurture twin studies?
Overall, genetics has more influence than do parents on shaping our personality. Molecular genetics is the study of which genes are associated with which personality traits. The largely unknown environmental influences, known as the nonshared environmental effects, have the largest impact on personality.
Why are twins different heights?
Some identical twins can have different heights and weights. This is because height and weight are controlled by what you eat as well your DNA. Differences in diet can start earlier than you might imagine. When the twins are growing inside the uterus, there can be differences in how well they connect to the placenta.
What is Twin method?
The twin method consists of a formal comparison between the resemblance between identical (monozygotic, MZ) twins and the resemblance between fraternal (dizygotic, DZ) twins for some trait of interest.
Do twins come from Mom or Dad?
According to Stanford, the likelihood of twins during any particular pregnancy comes from the mother, because, as they put it, “A father’s genes can’t make a woman release two eggs.” If you’re the woman who is trying to conceive though, it’s not just your mom’s genetics that matter.
What are identical twins called?
Identical or ‘monozygotic’ twins Twins conceived from one egg and one sperm are called identical or ‘monozygotic’ (one-cell) twins. The biological mechanisms that prompt the single fertilised egg to split in two remain a mystery.
What is concordance rates in twins?
Concordance, as used in genetics, usually means the presence of the same trait in both members of a pair of twins. However, the strict definition is the probability that a pair of individuals will both have a certain characteristic, given that one of the pair has the characteristic.
Why are twin studies useful?
Twins provide a valuable source of information for health and psychological research, as their unique relationship allows researchers to pull apart and examine genetic and environmental influences. … Twin studies allow researchers to examine the overall role of genes in the development of a trait or disorder.
Why are twin studies flawed?
Although the authors of psychiatry and psychology textbooks and other mainstream publications usually endorse genetic interpretations of psychiatric twin studies uncritically, there is a fatal flaw underlying these studies: identical twin pairs grow up experiencing much more similar environments than experienced by …
How do twin studies help establish heritability?
Researchers use this method, and variations on it, to estimate the heritability of traits: The percentage of variance in a population due to genes. Modern twin studies also try to quantify the effect of a person’s shared environment (family) and unique environment (the individual events that shape a life) on a trait.
Why dont identical twins look exactly the same?
We think of identical twins as having identical DNA. But, actually, twins who start out with identical DNA always have slightly different DNA by the time they’re born. … And they also each use their DNA a bit differently too.
How does the environment affect identical twins?
Any differences between identical twins is expected to be due to environmental factors since they are genetically identical, whereas fraternal twins only share half of their genes on average. … When an environmental influence is dominant, the trait similarity would be the same for identical and fraternal twins.
Can someone who is a twin have twins?
In general, it is fraternal (dizygotic or DZ) twins that run in families. … Identical twins don’t generally run in families, but fraternal twins do. It looks like twins “skip a generation” in some families. This is because genetic factors that may cause hyperovulation resulting in DZ twins can only be observed in women.