The information contained in this book is taken from my first book - "Catahoula Coat Color Genetics - Painting the Canvas."
As Merle testing has progressed and more information has become available, it became apparent that there was a need for a book devoted exclusively to MERLE.

Note - Many of the example pictures are of Catahoulas, however numerous Merle breeds are represented in the book. 

Introduction and History of Merle

The Shortening and Lengthening of Merle

Cryptic Merle - Possible Lengthening

Merle - The Saga Continues

Mh - Harlequin Merle

Vemodia - Laboratory of Molecular Veterinary Diagnostics

    "M" LOCUS Alleles

     m - Non-Merle - Wild Type     171 bp
     Mc - Cryptic Merle                     200 - 230 bp
     Mc+                                              231 - 246 bp
     Ma - Atypical Merle                   247 - 254 bp
     Ma+                                              255 - 264 bp
     M - Merle                                    265 - 269 bp
     Mh - Harlequin Merle                270 - 280 bp

Lethal White

Typical Merle Phenotype - Example Charts

Vemodia Test Results


The Shortening of Merle

The Lengthening of Merle

DNA Repair

Dilute or Atypical Merle

Merle in all Breeds

Ma and the Catahoula Breed