RFLP & AFLP

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JayanthaBandara
JayanthaBandara's picture
RFLP & AFLP

Please explain me the reason for the following.

RFLP is generally considerd as a codominent marker but AFLP is considered as a dominant marker.
In both cases restrction enzymes are used. So, there is a very big chance for AFLP to behave like a codominant marker. But mostly AFLP is described as a domonant marker

Thanks

Jayantha

Ivan Delgado
Ivan Delgado's picture
Hi Jayantha,

Hi Jayantha,

A dominant marker, by definition, allows for the analysis of many loci at a time, while a codominant marker only allows the analysis of a single locus per experiment. 

Although both AFLPs and RFLPs use restriction enzymes, they use them in very different ways. RFLPs use restriction enzymes to identify variations in DNA sequences within a single locus, while AFLPs use restriction enzymes to create a large population of DNA fragments which are then amplified to identify the presence of absence of various polymorphisms at different loci at the same time.

You could argue that an AFLP could behave as a codominant marker, but if it does it is not working properly or for that matter not being used to its full potential. In other words, if you are using an AFLP to study a single locus, then you are going through a lot of work to analyze a single genomic region that could be analyzed much easier by a simple PCR.

I hope this helps.

JayanthaBandara
JayanthaBandara's picture
 Thanks a lot for the reply

 Thanks a lot for the reply