Chromosome Abnormalities

Question 1

FISH probes

Answer 1

Centromeric probes - to determine number of chromosomes
Telomeric probes - for detecting subtelomeric rearrangements
Whole chromosome probes - for detecting translocations and rearrangements

Question 2

Structural chromosome abnormalities

Answer 2

Robertsonian translocation
Deletions
Inversions

Question 3

Acrocentric chromosomes

Answer 3

One arm is longer than the other

Question 4

Robertsonian translocation

Answer 4

In acrocentric chromosomes - results in one chromosome with both long arms while the other has both short arms

Question 5

Deletions

Answer 5

A section of the chromosome is removed

Question 6

Inversions

Answer 6

Paracentric - a section of DNA in the arm of the chromosome is removed
Pericentric - the DNA around the centromere of the chromosome is inverted

Question 7

Trisomy 21

Answer 7

Down’s syndrome

Question 8

Trisomy 18

Answer 8

Edward’s syndrome

Question 9

Trisomy 13

Answer 9

Patau syndrome

Question 10

X

Answer 10

Turner syndrome - neck webbing, widely spaced nipples, infertile, short stature, normal intelligence and lifespan

Question 11

XXY

Answer 11

Klinefelter syndrome - tall stature and long limbs, 50% develop breasts, infertile, small testes, mild learning difficulties