Lecture 2 - Genetic Variation + Detection

Question 1

2 types of MACRO variation

Answer 1

Numerical Aberration
Structural Aberration

Question 2

2 types of MEDIUM variation

Answer 2

Tandem Repeat Polymorphisms
INDEL polymorphisms

Question 3

4 common types of Numerical aberration

Answer 3

Triploidy - extra set of chromosomes
Trisomy - 3rd chromosome
Monosomy - missing a chromosome
Mosaicism - different genetics in cells

Question 4

3 types of structural aberrations

Answer 4

Deletions
Inversions
Translocation of DNA fragments

Question 5

2 types of Tandem Repeat Polymorphisms

Answer 5

Microsatellite - 1-6 bp repeated unit
Minisatellite - 11-100 bp repeated unit

Question 6

Properties of SNP’s (4 points)

Answer 6

Single Nucleotide Polymorphism
Accounts for 90% of genetic variation in humans
Majority are silent mutations
Each SNP has an rs number

Question 7

3 types of repetitive sequence

Answer 7

Unique
Moderate
High

Question 8

Properties of Unique repetitive sequences (2 points)

Answer 8

Found once/few times in genome
Includes structural genes

Question 9

Properties of moderately repetitive sequences (2 points)

Answer 9

Found a few hundred times in genome
Includes rRNA and histone genes/Ori/Transposable elements

Question 10

Properties of Highly repetitive sequences (3 points)

Answer 10

Found thousands of times in genome
Can be interspersed - e.g. Alu family
Can be clustered in tandem arrays - e.g. centromeric regions

Question 11

Definition of Tandem repeats

Answer 11

Copies which lie adjacent to each other, either directly of inverted

Question 12

Definition of Satellite DNA

Answer 12

Found in centromeres/heterochromatin

Question 13

Definition of Minisatellite

Answer 13

Repeat unit 10-60 bp long
Controls expression and gene structure

Question 14

Definition of Microsatellite

Answer 14

Repeat Unit of <10 bp long
Controls gene stability

Question 15

Definition of Interspersed Repeats

Answer 15

Transposable elements
Selfish - replicate without regard of environment/consequence using DNA machinery

Question 16

4 types of Transposable elements

Answer 16

Retrotransposons
LTR-retrotransposons (HERV’s)
Short Interspersed Nuclear Elements (SINE’s)
Long Interspersed Nuclear Elements (LINE’s)

Question 17

4 types of Length Polymorphisms

Answer 17

RFLP’s
VNTR’s
STR’s
Alu

Question 18

2 types of Markers

Answer 18

Biochemical - e.g. Blood Group
DNA Genetic Markers

Question 19

3 Steps of DNA Amplification

Answer 19

Denaturation at 95C
Annealing at 56C
Extension at 72C