THE KC has taken the decision not to register merle (dapple) as a colour in either Smoothcoat or Longcoat Chihuahuas, after meeting with various Chihuahua club’s throughout the UK to discuss the removal of potential problems.
Merle patterning, patches of lighter colour appearing in the coat, is the result of the M gene in the dog. There are two alleles of this gene: MM (merle) and M+ (non-merle), with merle being dominant to non-merle. In some breeds, the effect of the merle allele (MM) is termed ‘dapple’.
Unfortunately, the effects of the merle allele (MM) are not confined to coat patterning and we know that there can be an increased risk of impaired hearing and sight associated with it.
Many breeds are aware of and have for many years dealt perfectly adequately with avoiding the consequences of these health issues. However, because the colour has not hitherto been encountered in the United Kingdom in Chihuahuas, and the fact that it is not a natural colour in the breed, the General Committee of the Kennel Club has decided as a precautionary move to take this different approach.