Merle Testing Information


Vemodia Labs will identify and report 7 alleles on the M Locus - 

Mh, M, Ma+, Ma, Mc+, Mc and m.

Cost - 45/Euro - Approximately $55/US


Exact base pair numbers will be reported on results.

Non-Merle -              m - Wild Type

Cryptic Merle -          Mc     200 - 230 bp

                                    Mc+   231 - 246 bp

Atypical Merle -        Ma     247 - 254 bp

                                    Ma+  255 - 264 bp

Merle -                       M       265 - 269 bp

Harlequin Merle -     Mh      270 - 280 bp

This diagram will provide a good visual of where the alleles fall on the "scale" of Merle

Interpretation of the genetic description and terminology -

'Wild Type" - m/m - neither of the investigated alleles of the gene harbor SINE insertion

"Heterozygous Mutation" - one of the investigated alleles harbor SINE insertion, the other is wild type (without SINE insertion)

"Compound Heterozygous Mutation" - both investigated alleles of the gene harbor a SINE insertion

"Homozygous Mutation" - both investigated alleles of the gene harbor the same SINE insertion

You will receive a chromatogram of your dog's results - a "picture" which shows the peaks of where exactly the alleles fall on the locus.

Vemodia's testing also allows for the identification of a "mosaic" result - 3 or more alleles on the locus, due to a shortening of an allele early in development.

The following is an example of a dog who is a "mosaic" - 3 alleles on the Locus.
You will notice that the Mc allele has shorter peaks - Vemodia is referring to this as the "minor" allele. This dog should have tested as M/Ma from his parents, however either the M or Ma mutated (shortened) early in embryo development and created some cells that include Mc.
This "minor" allele on a mosaic test will be reported using square brackets [**].
This result is M/Ma/[Mc] - 267/252/[221]

Here is a M/[Mc]/m - 265/[208]/m result on a Catahoula.

This diagram explains the mechanism behind this Mosaic result.


You can order from Vemodia two ways -
Register an account with them and order the testing online.
Once completed the order will be emailed to you to be printed off and enclosed with the DNA sample.
The cost is 46 Euro - Approx $55/US and $70/Cdn (Depending on exchange rates.)
You will not be billed until after the results are emailed to you.
Payment can be made via credit card or PayPal - paypal@vemodia.cz


You also can download the following form to be filled in and enclosed with your samples without registering an account with them first.


They will accept blood or 3 buccal swabs - they do prefer cotton or rayon tipped sterile swabs over the brush type - these can be purchased from most pharmacies or your vet.
Q-tips can also be used from a new unopened box.
As well hair samples can be sent - use tweezers to pull hairs from 2 or 3 different areas of the body (approximately 20 hairs including roots are required) and enclose in a small paper envelope. If mailing from the US, it's easier to mail a hair sample as no custom's paperwork is require. When using swabs most post offices will require that a custom's document be filled out.

These are the swabs that I use.
These are the swabs that I use.

Samples can sent by regular mail.

Mailing Address - VEMODIA a.s.
                                V Hůrkách 2144/3
                                158 00
                                Prague
                                CZECH REPUBLIC