Atypical sex chromosomes

• atypcial sex chrosomes

  any sex chromosome that deviates from the usual xx or xy which tends to be associated with a distinct pattern of physical and psychological symptoms
• klinefelters syndrome

  affects 1 in 600 males. they have an additional X chromosome
• klinefelters physical characteristics

  physcial - reduced body hair, breast development and a rounding of body contours, longer limbs and underdeveloped genitals
• klinefelters psychological characteristics

  poorly developed language skills and reading ability, shy and lack interest in sexual activity

  tend to not respond well to stressful situation and may exhibit problems with executive functions such as memory and problem solving
• Turner’s syndrome

  affects 1 in 5000 females, caused by absence of short arm on x chromosome
• turners physical characteristics

  no menstural cycle, ovaries don’t develop so infertile, broad shield chest with no breasts, low set ears and webbed neck

  physically immature and retain appearance of prepubescent girls
• turners psychological characteristics

  higher than average reading ability

  lower spatial visual memory, and mathematical task ability

  socially immature and have trouble relation to peers
• strength of atypical sex chromosome syndromes is its contribution to the nature-nurture debate

  By comparing people who have these syndromes, with people who have typical chromosome, your able to see behaviour and psychological differences. It might be logically inferred that these differences have a biological basis

  This supports the innate nurture side of the debate
• there are issues leaping to the conclusion of a biological basis

  envrionmenatl and social influences may be responsible for the behavioural differences observed

  for example, social immaturity in turners girls may be because they are treated immaturely by the people around them because of their prepubescent appearance
• a strength is the real world application

  continued research into atypical chromosome patterns is likely to lead to earlier and more accurate diagnosis as well as a more positive outcome in the future

  An Australian study of 87 Klinefelter males showed that those who had been identified a treated from

  a very young age experienced significant benefits in terms of managing their syndrome compared to those diagnosed in adulthood
• a limitation with the description of Klinefelters is there may be some sampling issues

  to identify the characteristics of XXX individuals, you have to identify a large number of individuals with

  the disorder in a database.

  In general, only those people who have the most severe symptoms are identified a therefore the picture of typical symptoms may be distorted

  This means the typical picture of Klinefelters may be exaggerated.