Problem 1 - Abnormal Psychology: An Integrative Approach

Question

Check your understanding of genetic vulnerability by filling in the blanks of the statements associated with family, twin, and adoption studies. Choose from (a) higher, (b) lower, (c) equal, (d) severity, (e) type, (f) identical twin, (g) specific, (h) fraternal twin, and (i) general. The greatest risk of having schizophrenia is in those who have a(n) ____________ or ____________ with schizophrenia. Any relative with schizophrenia will make your chances of developing the disorder ____________ than those of the general population.

Step-by-Step Solution

Answer

Identical twin, fraternal twin, higher.

Step 1: Understand the Statements

The first statement is about identifying the family relationships with the highest risk of schizophrenia. The second statement involves comparing the risk of developing schizophrenia for someone with a relative with the disorder, against the general population.

Step 2: Identifying Key Relationships

The options (f) "identical twin" and (h) "fraternal twin" are family relationships. Of these, having an (f) "identical twin" with schizophrenia poses a higher risk than a (h) "fraternal twin," because identical twins share 100% of their genes.

Step 3: Fill in the First Blank

From Step 2, the greatest risk is associated with having an (f) "identical twin" with schizophrenia, so fill in the first blank with 'identical twin.'

Step 4: Fill in the Second Blank

Since Step 2 confirmed that (f) "identical twin" represents the greatest risk, fill the second blank with the second highest risk category from the options, which is having a (h) 'fraternal twin.'

Step 5: Comparing Risk with the General Population

The third statement involves comparing risk levels: "Any relative with schizophrenia will make your chances of developing the disorder ________ than those of the general population." The risk will be (a) "higher" if there’s any family history of the disorder, which is the correct fit here.

Step 6: Fill in the Blanks

Now, fill the first two blanks with (f) 'identical twin' and (h) 'fraternal twin,' and the third blank with (a) 'higher' according to the explanations above.

Key Concepts

Family Studies

Family studies help us understand how some disorders, like schizophrenia, run in families. When scientists conduct these studies, they look at many family members across different generations. The objective is to see how often a disorder occurs among relatives.
Doing so helps determine the genetic link of the disorder. Usually, the closer you are genetically to a family member with a disorder, the higher your risk is too.
This is because you share more genes with closer relatives. Key Features of Family Studies:

• They span multiple generations, looking at parents, children, siblings, and even grandparents.
• They assess the frequency and types of disorders within a family.
• Data from these studies help compare risks among relatives to the general population.

Even though these studies provide valuable information, genetic vulnerability isn't solely determined by genes; environmental factors also play a role.

Twin Studies

Twin studies are a powerful way to understand genetic influences on certain disorders. They involve comparing identical twins, who share 100% of their genes, with fraternal twins, who share about 50% of their genes. This comparison helps researchers discern the influence of genetics versus the environment.
When we see that both twins often share a disorder, it suggests a strong genetic component.
However, differences between identical and fraternal twins can also highlight the role of environment. Factors Considered in Twin Studies:

• Concordance Rates: The probability that one twin has a disorder if the other does.
• Discrepancies between identical and fraternal twins in disorder occurrence.

These studies have shown that if one identical twin has schizophrenia, the other twin has a significantly higher risk of developing it compared to fraternal twins or siblings. Although genetics play a crucial role, it’s essential to remember the environment also influences outcomes.

Adoption Studies

Adoption studies take a different approach by analyzing children adopted away from their biological parents. This allows researchers to separate the effects of genetics from the environment more clearly. Because adoptees grow up in environments different from their biological parents, any similarities in disorders can be attributed more to genetics than upbringing. Significance of Adoption Studies:

• Provide clear evidence by comparing similarities between adoptees and their biological vs. adoptive families.
• Help in understanding the genetic basis of disorders without environmental contamination.

For example, if a child adopted away has a biological parent with schizophrenia and develops the disorder themselves, it suggests a genetic link. Adoption studies are thus crucial in detailing genetic vulnerabilities, while also underlining that genetics isn't the sole determinant, and upbringing can still play an influential role.