ABNORMAL BEHAVIOR
SCHIZOPHRENIA
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
In MZ twins who are raised in different environments do not develop schizophrenia depending on the nurture
|
|
|
In MZ twins the co-twin was just as likely to be schizophrenic if the the other twin was separated from him/her
|
|
|
50% of DZ twins had a shared schizophrenic status despite differences in the environment
|
|
|
The MZ has about 50% chance to develop schizophrenia if the other twin is diagnosed with it whether they have the same environment or not.
|
Detailed explanation-1: -[2] Analyzing classic studies of the genetics of schizophrenia done as early as in 1930s, Fischer concludes that a concordance rate for psychosis of about 50% in monozygotic twins seems to be a realistic estimate, which is significantly higher than that in dizygotic twins of about 10–19%.
Detailed explanation-2: -In identical twins, if a twin develops schizophrenia, the other twin has a 1 in 2 chance of developing it, too. This is true even if they’re raised separately. In non-identical twins, who have different genetic make-ups, when a twin develops schizophrenia, the other only has a 1 in 8 chance of developing the condition.
Detailed explanation-3: -Heritability is the proportion of variance explained by genetic factors. The concordance rates of schizophrenia for monozygotic twins have been found to be about 40 to 50%, and heritability estimates are around 80% 46, 47.
Detailed explanation-4: -Among biological factors, genes play an important role. Twin studies have shown that genetic factors account for about 80 percent of an individual’s risk of developing schizophrenia.