Atypical Sex Chromosome Patterns Flashcards
What are atypical sex chromosome patterns?
Any sex chromosome pattern that deviates from the usual XX/XY formation and which formation and which tends to be associated with a distinct pattern of physical and psychological symptoms.
What is Klinefelter’s syndrome?
A syndrome affecting males in which an individual’s genotype has an extra X chromosome, characterised by a tall thin physique, small infertile testes, and enlarged breasts. 1 in 500-1000
What are the physical characteristics of Klinefelter’s syndrome?
Breast development, rounding of body contours, underdeveloped genitals.
What are the psychological characteristics of Klinefelter’s syndrome?
Poorly developed language skills and reading ability, lack interest in sexual activity.
What is Turner’s syndrome?
A chromosomal disorder in which effected women have only one X chromosome, causing developmental abnormalities and infertility. 1 in 5000
What are the physical characteristics of Turner’s syndrome?
No menstrual cycle
Ovaries are sterile
No breasts and broad chest
Webbed neck
What are the psychological characteristics of Turner’s syndrome?
Higher than average reading ability
Socially immature
What is the evaluation for atypical sex chromosome patterns?
Nature-nurture debate
Environment explanations
Practical application
Unusual samples
Evaluation point: Nature-nurture debate
By comparing people who have these conditions with chromosome-typical individuals it becomes possible to see psychological and behavioural differences between the two groups. It can be inferred that these differences have a biological basis and are a direct result of abnormal chromosomal structure.
This would suggest that innate ‘nature’ influences have a powerful effect on psychology and behaviour.
Evaluation point: environment explanations
It may be that environmental and social influences are more responsible for the behavioural differences seen.
E.g. social immaturity in TS may be due to people treating them differently due the pre-pubescent appearance, hence encouraging immaturity.
This shows that it is wrong to assume that observed psychological and behavioural differences due to nature.
Evaluation point: practical application
Continued research is likely to lead to earlier and more accurate diagnosis.
An Australian study of 87 individuals with KS showed that those who were identified and treated from a younger age had significant benefits to those treated in adulthood.
This suggests that increased awareness of these conditions may have practical application
Evaluation point: unusual sample
The main issue is the lack of generalisability from atypical individuals to the wider population.
It is also the case that individuals who look different are unlikely to be treated in the same way as their peers.
This may make it difficult to asses the contribution of nature and nurture in terms of psychological differences
