Chromosome abnormalities, mutations and analysis

Question 1

Highest Incidence of chromosomal abnormalities

Answer 1

First-trimester miscarriages (trisomy 16 most common) and then children with mental retardation

Question 2

3 types of chromosomal abnormalities?

Answer 2

numerical, structural and mutational

Question 3

Trisomy 47 XX +13

Answer 3

Patau syndrome

Question 4

Trisomy 47 XY +18

Answer 4

Edwards

Question 5

Trisomy 47 XX +21

Answer 5

Down (autosomal aneuploidy)

Question 6

Trisomy 47 XXY

Answer 6

Klinefelter

Question 7

Trisomy 45 X

Answer 7

Turner

Question 8

1st meiotic division error, homologous pair do not separate properly e.g.21 - addition/deletion
or
2nd meiotic division error

Answer 8

Non-disjunction error

Question 9

fusion of two acrocentric chromosomes

Answer 9

Robertsonian translocation

Question 10

involves breaks in 2 chromosomes with formation of 2 new derivative chromosome

Answer 10

reciprocal

Question 11

purine to purine point mutation

Answer 11

transition

Question 12

purine to pyrimidine point mutation

Answer 12

transversion

Question 13

What do we need for PCR?

Answer 13

Sequence information
Oligonucleotide primers
DNA
Nucleotides
DNA polymerase

Question 14

Restriction fragment length polymorphism (RFLP) analysis

Answer 14

Detecting mutations - sickle cell anaemia diagnosis

Question 15

Normal + constitutive primer = amplification

mutant + constitutive primer = no amplication

Answer 15

Amplification refractory mutation system (ARMS) - Detecting mutations

Question 16

ds DNA - Denature, Anneal and Extend using DNA polymerase (rpt 20-30 times)

Answer 16

PCR

Question 17

Restriction endonucleases

Answer 17

enzymes from bacterial cell, degrade DNA of virus, cut DNA at same site, protective mech, recognise spec DNA seq

Question 18

gold standard for mutant detection - chain termination method - use of ddNTP

Answer 18

gene seq

Question 19

separate DNA fragments by size

Answer 19

gel electropherosis