atypical chromosome patterns

• Klinefelter syndrome (XXY)

  Affects males, 1 in 660. Physical characteristics -> tall, overweight, enlarged breasts, lack facial/body hair, small testes: usually infertile. Psychological effects -> language issues, slower to lean how to speak, may find reading & writing difficult, low self-esteem. Treatment -> testosterone replacement therapy.
• Turner's syndrome (X0)

  Females, affects 1 in 2000. Physical characteristics -> short, ovaries may not develop/infertile, webbed neck, heart defects. Psychological effects -> above average reading ability, below average maths skills, socially immature. Treatment -> growth hormones, oestrogen replacement.
• Support for atypical chromosome patterns

  DeLisi - performed an MRI scan on 11 people with Klinefelter's syndrome & 10 without. Those with Klinefelter's syndrome showed structural differences in the brain which may account for the language impairment. Supports the view that Klinefelter's syndrome may affect psychological development. Sample was small so may not be representative of other individuals with Klinefelter's making generalisation difficult.
• Atypical chromosome patterns - evaluation: strengths

  Studying people with Turner's syndrome & Klinefelter's syndrome might help our understanding of gender because by studying people with atypical sex chromosomes & comparing their development with that of people with typical sex chromosomes, psychologists are able to establish which types of behaviour are genetic.
• Atypical chromosome patterns - evaluation: weaknesses

  • Need to be cautious generalising from research conducted on people with Klinefelter's or Turner's as those who come forward for research may not be typical of people with the conditions
  • Due to looking physically different, people with these conditions may get treated differently from their peers, so it is difficult to disentangle nature/nurture
  • Girls with Turner's syndrome are socially immature & have issues fitting in socially, however this could be due to nurture rather than nature as people may interact with someone with Turner's syndrome in a more immature way due to how they look
  • This challenges the view that all symptoms of Turners must be biological in nature