Atypical Sex Chromosome patterns

Question 1

Give a brief description of klinefelters syndrome.

Answer 1

Affects 1 in 750 biological males. It isn’t inherited but thought to be caused by an error during meiosis where an egg or sperm cell ends up with an extra X chromosome. 2/3 cases go undetected, as cases go not noticed til puberty which is late or incomplete.

Question 2

Physical symptoms of klinefelters (6)

Answer 2

Clumsiness
Reduced body hair
Gynecomastia
Extra height 
Long limbs 
Underdeveloped genitals

Question 3

Psychological symptoms of klinefelters (7)

Answer 3

Poor language skills
Poorly developed reading
Passive and shy
Low libido
Memory problems
Easily upset
Problem solving abilities

Question 4

Describe research into klinefelters

Answer 4

DeLisi studied 11 participants with and 11 participants without klinefelters. They took part in a psychiatric interview, cognitive tests and an MRI scan. They found abnormalities in various brain areas of most males with klinefelters.

Question 5

Give a brief description of Turners syndrome.

Answer 5

Affects 1 in 2500 biological females. Have one X chromosome; X0.

Question 6

Physical symptoms of turners syndrome (8)

Answer 6

Amenorrhea
Low set ears
Broad chest
No breast development 
Infertility
Webbed neck
High hip to waist ratio
Appearance of pre-pubescent girl

Question 7

Psychological symptoms of turners (5)

Answer 7

Poor spatial/visual memory
Poor math skill
Socially immature
Difficulty with peer relationships
Higher reading/language ability

Question 8

Describe research into turners syndrome

Answer 8

Brown et al conducted MRI scans on 26 girls with turners syndrome and 26 age matched girls without. Girls with turners ha smaller cerebral and cerebellar brain areas, suggesting it affects growth of certain parts of the brain, linked to developmental affects seen w the disorder.

Question 9

Give the SCIP of atypical sex chromosome patterns.

Answer 9

S: research: DeLisi and Brown
C:relationship between atypical patterns and differences in behaviour is not causal, e.g. Girls with turners syndrome may be treated immaturely due to their appearance which could cause development problems. (Social factors)
I: socially sensitive - prenatal discovery may lead to termination
p: study of 87 Australians with klinefelters showed those diagnosed early had significant benefits. Also testosterone given to those with klinefelters and oestrogen and growth hormone injections to girls with turners - implication for economy.