Atypical sex chromosome patterns Flashcards
(11 cards)
What are atypical chromosome patterns?
Any sex chromosome pattern that deviates from the usual XX/XY formations
Tends to be associated with a distinct pattern of physical and psychological symptoms
What is Klinefelter syndrome?
Affects 1/600 males
Biological males - anatomical appearance of a male
Additional X chromosome so XXY
10% identified by prenatal diagnosis
2/3 of people who have this are not aware of it
Diagnosis often accidental
What are physical characteristics of Klinefelter’s syndrome?
Reduced body hair
May be some breast development at puberty
Softening or rounding of body contours
Long gangly limbs
Underdeveloped genitals
Problems with coordination and clumsiness
Susceptible to health problems that are more commonly found in females - such as breast cancer
What are psychological characteristics of Klinefelter’s syndrome?
Poor developed language skills and reading ability
Passive
Shy
Lack interest in sexual activity
May not respond well in stressful situations
Exhibit problems with executive functions - memory and problem solving
What is Turners syndrome?
1/5000 biological females
Absence of one of the two allotted X chromosomes
So XO
Affected individuals have 45 chromosomes instead of 46
What are physical characteristics of Tuners syndrome?
Don’t have menstrual cycle
Ovaries don’t develop - infertile
Don’t develop breasts
Broad shield chest
Low set ears
Webbed neck
High waist-to-hip ratio
Physically immature - retain appearance of prepubescent girls
What are psychological characteristics of Turners syndrome?
Higher than average reading ability
Performance on spatial, visual memory and mathematical tasks lower than average
Socially immature
Trouble relating to peers and experience difficulty fitting in
What is a strength of atypical sex chromosomes?
Contribution to the nature-nurture debate
Comparing makes it possible to see psychological and behavioural difference
Logically inferred these differences have a biological basis - direct result of the abnormal chromosomal structure
Supporting view that innate nature influences have a powerful effect on psychology and behaviour
What is a negative of atypical sex chromosomes?
Issues in leaping to biological conclusion
Not a casual relationship
Environmental and social influences more be more responsible for the behavioural differences observed
Eg. social immaturity seen in females with turner syndrome may arise from being treated immaturely by people around them
May have indirect impact upon their performance at school
Could be wrong to assume that psychological and behavioural differences are due to nature
What is a strength of atypical sex chromosomes?
Real world application
Continued research more likely to lead to earlier and more accurate diagnoses
More positive outcomes in the future
Australian study
87 individuals with Klinefelters syndrome
Those who had been identified and treated from a very young age experienced significant benefits in terms of managing their syndrome compared to those diagnosed in adulthood
Increased awareness of atypical chromosome patterns does have a useful real world application
What is a negative of atypical sex chromosomes?
Sampling issue
People with most severe symptoms are identified
Picture of typical symptoms may be distorted
Boada et al
Other studies produced more accurate picture of characteristics
Klinefelter syndrome - many don’t experience significant cognitive or psychological problems and are successful academically
Suggesting typical picture of Klinefelter may well be exaggerated
