Mapping

Question 1

Frequency of recombination is

Answer 1

Proportional to the physical distance apart

Question 2

Phase:

Answer 2

On the same chromosome

Question 3

Haplotype:

Answer 3

Order of in phase alleles along chromosome

Question 4

Linkage maps created by:

Answer 4

Determining the relative position of genetic markers by frequency of marker separation during meiosis through generations

Question 5

Human genome measure in:

Answer 5

cM centimorgan
1 cM = recombination fraction of 1/100 meioses
Physical equivalent to between 0.7 and 1 Mb of DNA

Question 6

What is the odds of linkage?

Answer 6

The ratio between the likelihood of two loci begin linked at a certain distance vs the likelihood they are not linked at all
The logarithm of odds
LOD score (Z) is the standard unit o linkage

Question 7

Genetic mapping of disease causing mutant genes

Answer 7

Identify affected family/families
Determine pattern of inheritance (pedigree)
Isolate chromosomal DNA (genomic) from each person
Carry out genetic mapping; find out which markers co-segregate with disease
Deduce approximate locus of gene

Question 8

Genetic maps provide a rough idea where a disease gene is Eventually you will want to work with physical DNA by:

Answer 8

I you know approx. where disease gene is and now you want to clone it I.e identify it
Allows start of human genome project

Question 9

Huge quantities o DNA kept in:

Answer 9

A library (storage/duplication/distribution)
A database (relationships)

Question 10

Making a DNA clone library

Answer 10

1. Break up Han DNA into small fragments using restriction digest
2. Place each fragment in a vector (cloning step) which is a DNA sequence that an replicate in a prokaryotic host
3. Store in bacterial or yeast cells as clone libraries
4. will form clonal populations - these can be stored, analysed or further propagated
5. Can also make libraries from mRNA found in a tissue. Convert to cDNA then clone. A cDNA library representing all genes expressed

Question 11

How do you turn a library into a true physical map?

Answer 11

Relationships
Use bacterial/yeast clones as probes for FISH…tells you where they are located and on which chromosomes
Which genetic markers do they contain?
Which ones overlap? Chromosome walking! A Contig

Question 12

Ask are the alleles of the two microsatellite loci alway inherited together, mostly or 50/50 chance?

Answer 12

This indicates complete, partial or no linkage