Labrador plata

There are two ways that a new gene could appear in a closed register of pedigree dogs.

• Spontaneous genetic mutation
• Outcrossing

Genes can mutate.  We know that.

For a mutation that occurred spontaneously to create a new gray Labrador coat color would be unusual, but not impossible.
For the  mutation to be identical to a gene that already exists for an unusual coat color in another breed would be something of a coincidence.  So what about outcrossing?

The fact is, the dilution gene found in Labradors now, is the exact same gene that gives us the coat dilution in Weimaraners.

Many people feel that the spontaneous appearance of this dd  dilution gene, in the Labrador Retriever  gene pool is to say the least unlikely.
Fuente: https://www.thelabradorsite.com/silver-labradors/

Some dogs with dilute color display minimal or no health problems; other dogs experience hair loss and skin problems. Color dilution alopecia (CDA) and black hair follicular dysplasia (BHFD) can accompany coat color dilution. These diseases cause recurrent skin inflammation and drying, bacterial infections of hair follicles and severe hair loss.

Other disorders that could travel with the dilution gene are heritable Weimeraner genetic issues such as trembling disorders, autoimmune related vaccination sensitivity and intolerance, Von Willebrands Disease, hyperuricosuria causing painful bladder and kidney disease, and behavioral problems that are more common in the Weimaraner  such as separation anxiety, and dominant, protective, territorial temperament. Minimizing occurrence of these conditions would mean minimization of the dilute mutation.