Atypical Sex chromosome patterns Flashcards
What is Klinefelter syndrome (chromosomes?
-XXY chromosomes (extra X)
-47 chromosomes, not 46
How many males are affected by KF syndrome and b) how many dont know they have it?
-affects 1/600 males
–2/3rds of people dont know they have KF
What are physical characteristics of KF?
-Long gangly limbs
-gynaecomastia
-softening and rounding of body contours
-underdeveloped testes
-Not alot of body hair
-Problems with coordination and general clumsiness
Psychological characteristics of KF
-poorly developed language and reading skills
-passive and shy
-lack interest in sexual activity
-dont respond well to stressful environments
-exhibit problems with “executive functions” such as problem solving and memory
What is Turner Syndrome?
-X0 ( missing one x chromosome)
-45 chromosomes not 46
How many girls are effected by Turners syndrome?
-affects 1/5000 females
Physical characterisitcs of Turner’s syndrome
-appearance of pre-pubescent girl
-Webbed neck
-broad shield chest instead of breasts
-ovaries are not developed and therefore are infertile and dont have a menstrual cycle
- high waist-to-hip ratio- hips are not much bigger than waist
Psychological characteristics of Turner’s syndrome
-higher than average reading ability
-spatial, visual and mathematical ability lower than average
-socially immature and struggle to fit in
Strengths of research of atypical chromosome pattern
-Nature and nurture debate:research reveals that individuals with Turner’s syndrome tend to have higher verbal ability and talk more than ‘typical’ girls.This means that psychological and behavioural differences observed in individuals with these syndromes may have a biological basis due to their chromosomal structure.Therefore, this suggests that innate ‘nature’ influences have a powerful effect on psychology and behaviour.
-Real world application: More reasearch into atypical patterns may lead to more accurate and early diagnoses. Herhily et al (2011) - an Australian study of 87 individuals with KF showed that those who had been identified and treated from a young age experienced significant benefits in terms of those managing their syndrome compared to those diagnosed in adulthood.
Limitations of research of atypical chromosome patterns
Counter to nature- nurture debate: may not be causal Environmental influences may be responsible for behavioural differences observed. E.g. social immaturity in Turner girls may be because people treat them immaturely because of their appearance as a pre-pubescent girl Therefore the assumption that the differences are because of nature may be misled.
-Sampling issue:important to create a big database of individuals to understand range of symptoms but in general only those with most severe symptoms have been identified with may skew understanding of the conditions. Boada et al. (2009) report that prospective studies find that most people with KF do not have cognitive problems and many are highly academically successful. Therefore, KF may be exaggerated.
