Merle Testing Information


Tilia Labs (formerly Vemodia) will identify and report 7 alleles on the
M Locus - 

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

Cost - 47/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 - 268 bp

Harlequin Merle -    Mh      269 - 280 bp

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

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

The following is an example of a dog who is a "Mosaic Merle".
You will notice that the Mc allele has a shorter peak - this is referred to this as the "minor" allele - the allele with the least percentage of cells present in the sample material.
This dog should have tested as Ma/M 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 [Mc]/Ma/M - [221]/252/267

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

This diagram explains the mechanism behind this Mosaic result.


Tilia homepage for registering an account.


You may also order a test without setting up an account by using the following link.

Note - Chip Number, Tattoo Number and Identification are required fields - if none apply then the fields can be filled in with "n/a". 


Tilia will accept blood, dew-claws/docked tails or 3 buccal swabs - 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 30 hairs including roots are required) and enclose in a small paper envelope (Preferably do not use a plastic baggie as static causes the hairs to cling to the bag.)
If mailing from the US, it's easier to mail a hair sample as no custom's paperwork is required. When using swabs most post offices in the US will require that a custom's document be filled out.
Please do not enclose swabs in a plastic baggie due to the trapped moisture causing mold.

Samples can sent by regular mail using an international stamp.

TILIA LABORATORIES s.r.o.
5. května 44
273 08 Pchery
Czech Republic

You will be invoiced after your results have been received via email.
Payment can be made using PayPal - 
info@tilialaboratories.cz