DNA Markers Flashcards
(16 cards)
What is a Molecular marker?
It is a specific DNA sequence that is used to distinguish between different individuals and populations.
A specific piece of DNA that gives a unique piece of information.
What are the main three molecular markers?
Gene region
SNP’s
STR’s
What is a gene region?
It is a type of molecular marker and the gene has a specific/ known location on a chromosome.
Each site represents a single nucleotide polymorphisms.
Good at identifying different genes.
What are SNPs and what do they stand for?
They Stans for single nucleotide polymorphisms.
They are a single site in the human genome that variation can occur.
What is polymorphism?
The presence of genetic variation within a population.
What are advantages and disadvantages of SNP’s?
Some advantages include that there is a low mutation rate and there is a high abundance.
A disadvantage is that they are expensive to isolate.
What are STR’s?
They stand for Short Tandem Repeats.
They are a biological marker and they are a sequence of DNA that is repeated multiple times.
What is STR heyerozygote?
When the fragments are different sizes and there are two different alleles of a particular gene.
One allele inherited from both the male and female parent.
What is a STR homozygote?
The fragments are the same size and the individual has two identical alleles on a particular gene.
How will a homozygote and heterozygote STR be represented on a genetic analyser?
Homozygote: one peak
Heterozygote: two peaks
Define PCR and what it does.
It stands for polymerase chain reaction.
It is a process where DNA is amplified and millions of copies are produced.
What are the three processes that take place during PCR?
Denaturation
Annealing
Extension
What types of light soures can be used to visualise DNA?
Fluorescence Detection
Where are the DNA samples deposited in after amplification takes place?
In the wells of the agarose gel.
Which electrode does DNA move towards too as it is deposited into the agarose gel wells?
As DNA is negatively charged it will move towards the anode which is the positive electrode.
What is fragment length analysis?
It is a technique used to determine the size and length of DNA fragments.
It is very similar to agarose gel however the sizing the accuracy is better.
