Atypical Sex Chromosomes Flashcards
What are atypical sex chromosome patterns?
Any chromosome pattern that deviates from the usual XX/XY formation and which tend to be associated with a distinct pattern of physical and psychological symptoms.
Name two conditions caused by atypical sex chromosome patterns
- Klinefter’s syndrome
* Turner’s syndrome
Why do we study people with atypical sex chromosome conditions?
Studying people with ‘abnormal’ sex chromosome patterns allows us to gain a unique insight into how sex chromosomes (nature) affect gender behaviour. If they show different gender behaviours to people with typical chromosome patterns we can assume that gender is affected by sex chromosomes (nature).
What is the atypical chromosome pattern of Klinefter’s syndrome?
XXY
Extra X chromosome
What sex identity does Klinefelter’s effect
Males only (because of the Y chromosome)
What are the physical characteristics of Klinefelter’s syndrome?
- Lack of ability to grow facial and public hair
- Breast development at puberty and a softening/rounding of the body contours
- Underdeveloped genitals
- Long legs and arms in relation to their torso and have a problem with clumsiness and coordination
How is Klinefelter’s treated?
It is treated with testosterone supplements, allowing them to live relatively normal lives, though below-average lifespan
What are the psychological characteristics of Klinefelter’s syndrome?
- Poor language skills and reading ability
- Passive, shy and lack interest in sexual activity
- Attention problems
- increased risk of anxiety disorders and depression
How many males does Klinefelter’s syndrome affect?
It affects about 1 in 750 males
What is the atypical chromosome pattern of Turner’s syndrome?
X0
Absence of one of the two X chromosomes
Which sex identity does it affect?
Females
Lack of Y chromosome
What are the physical characteristics of Turner’s syndrome?
- Ovaries fail to develop and are sterile
- Do not develop breasts at puberty
- Shorter than average
- Low set ears
- Webbed neck
- Organ abnormalities especially in the heart and kidneys
What are the psychological characteristics of Turner’s syndrome?
- Higher than average reading ability
- Lower than average performance on spatial and mathematical tasks
- Socially immature/ trouble relating to peers
How is Turner’s treated?
Administering growth hormones and oestrogen allow sufferers to live relatively normal lives with only slightly reduced average life span
How many females does Turner’s syndrome affect?
Approximately 1 in 5000 females
EVALUATION OF ATYPICAL SEX CHROMOSOME PATTERNS
Evaluate atypical sex chromosome patterns’ contribution to the nature-nurture debate
A strength is that studying people with atypical sex chromosome patterns contribute to our understanding of the nature-nurture debate in gender development.
By comparing chromosome-typical and atypical individuals we can see the psychological and behavioural differences between them. This allows researchers to see what aspects of biological development and behaviour are influenced by genetics and chromosomes.
This is a strength as it supports the role of biology and nature in explaining gender development.
EVALUATION OF ATYPICAL SEX CHROMOSOME PATTERNS
Evaluate why it is oversimplified to assume that nature is the sole cause
A weakness is that it is possible that the impacts of environmental and social influences are more important in the behavioural differences seen than the research suggests.
For example, social immaturity in females with Turner’s syndrome may be due to the way others respond to their physical immaturity rather than to a biological cause related to their chromosomes. They may be treated in a way that encourages immaturity.
This suggests that it may be oversimplified to assume that psychological and behavioural differences are due to nature alone.
EVALUATION OF ATYPICAL SEX CHROMOSOME PATTERNS
Evaluate atypical sex chromosome patterns’ practical application
Research into patients with KS and TS has seen the development of relevant therapies.
For example, treating the stunted physical growth often seen with TS by the application of growth hormones and treatment of KS with testosterone, which has seen those with the condition develop a less passive nature.
This is a strength as it shows how knowledge of sex hormones has led to to treatments which improve both the quality and duration of their lives.
EVALUATION OF ATYPICAL SEX CHROMOSOME PATTERNS
Evaluate the sample
A limitation is that the samples are unrepresentative and atypical.
Individuals with unusual conditions, particularly those that impact their physical appearance, are unlikely to be treated the same way as their peers. This makes it difficult to disentangle the effects of nature and nurture when looking at gender differences.
Overall this makes it difficult to generalise from atypical individuals to the wider population.
EVALUATION OF ATYPICAL SEX CHROMOSOME PATTERNS
Evaluate exaggerated ‘typical’ gender behaviour
A limitation is that typical sex and gender may have been exaggerated.
The presumed contribution of Turner’s and Klinefelter’s syndrome to the nature-nurture debate is based on the idea that there are ‘typical’ gender behaviours associated with males and females.
(For instance, the idea that Turner’s individuals are socially immature is based on the idea that there is a typical level of social maturity for the vast majority of females)
A limitation is that the effect of atypical sex chromosomes may be based on stereotypical assumptions of what constitutes ‘average’ or ‘normal’ behaviour for males and females, rather than fact.
