ATYPICAL SEX CHROMOSOME PATTERNS

Question 1

What are atypical sex chromosomes?

Answer 1

Any sex chromosome pattern that deviates from the usual XX/XY formation. These are associated with physical and psychological symptoms.

Question 2

Why should we study these chromosomal abnormalities?

Answer 2

• Psychologists can compare people with typical sex chromosome patterns to people with atypical sex chromosome patterns
• Inferences may then be made as to whether or not differences in gender may be biological/chromosomal which helps to develop the argument about whether gender is as a result of nature or nurture

Question 3

Name 2 atypical sex chromosome patterns

Answer 3

Turner’s syndrome
Klinefelter’s syndrome

Question 4

Which characteristics are affected?

Answer 4

Physical
Psychological

Question 5

How many people are affected by Klinefelter’s syndrome?

Answer 5

It affects between 1 in 500 to 1 in 1000 people.
2/3 of people are unaware they have it

Question 6

What is the chromosome structure for someone who has Klinefelter’s?

Answer 6

XXY – additional X chromosome on 23rd pair

Question 7

What are the physical characteristics of Klinefelter’s syndrome?

Answer 7

• reduced body hair compared to an average male
• long limbs
• gynecomastia (breast development at puberty)
• under-developed genitals
• problems with co-ordination and general clumsiness
• softer and rounder body shape
• more susceptible to breast cancer

Question 8

What are the psychological characteristics of Klinefelter’s syndrome?

Answer 8

• poor reading abilities
• poor language skills
• do not respond well to stressful situations
• poor memory + problem solving abilities
• passive + shy

Question 9

How many people are affected by Turner’s syndrome?

Answer 9

Affects around 1 in 5000 females

Question 10

What is the chromosome structure for someone who has Turner’s?

Answer 10

There is a complete absence of one of the 2 X chromosomes - this is called XO. Therefore, people affected have 45 chromosomes rather than 46.

Question 11

What are the physical characteristics of Turner’s syndrome?

Answer 11

• no menstrual cycle (amenorrhoea)
• sterile due to lack of development of ovaries
• webbed neck
• do not develop breasts
• hips not much bigger than waist
• appearance of a pre-pubescent girl

Question 12

What are the psychological characteristics of Turner’s syndrome?

Answer 12

• higher than average reading ability
• difficulty fitting in and often loners
• socially immature
• poor spatial awareness
• poor memory + mathematical skills