Double Dapples: What Are They? Can You Breed Them?

If you have ever googled dapple dachshunds, then you likely have heard of double dapples, or DDs. Double dapples are the product of a dapple to dapple (or merle to merle) breeding, and are at risk for being born without eyes, blind, deaf, or with skin problems due to hereditary issues associated with the merle gene (M). Double dapples are dachshunds that have two copies of the dominant merle allele (MM) and therefore their offspring will all be dapples, whereas single dapple dachshunds' offspring have a 50% chance to be dapple. Many believe that breeding any dapple dachshund to another dapple dachshund will result in deformed puppies, but this is not always the case. In fact, it is possible to breed dapples to dapples with zero risk of complications to the puppies.

The amount of dappling on a dachshund is determined by something called the sine insertion. The length of this sine insertion will determine the colour of a dapple dachshund, or how many splotches of colour it has on it. Dachshunds that are not dapple will not have a sine insertion. The sine insertion length is measured on a bp scale from 200-280, with 200 being the least severe. Genetic tests, such as the ones offered by UC Davis, can determine the sine length of your dapple dachshund. 

Dapple dachshunds can have different alleles that can represent their sine length and determine what type of dapple they are. For example, the allele M (typical/classic merle) will give a dachshund a medium or average amount of dappling, while the allele M^h (harlequin merle) will usually give a dachshund lots of dappling and sometimes with large white patches, pigment loss, and/or blue eyes. Harlequin dapples can be confusing at times because their coat patterns tend to be very unpredictabl compared to other sine lengths. Some harlequin dapples have almost no dappling, while others have so much that they also have large patches of diluted white! A harlequin dapple occurs when the merle gene dilutes the background pigment to white. This is especially apparent in Harlequin merle Great Danes. Harlequin dapples are often mistaken as double dapples or as piebald dapples. However, harlequin dapples or double dapples can produce pigment loss on the eyes and nose, resulting in pink skin, whereas piebald usually does not delete pigment in these areas. Piebald dachshunds should have chocolate or black noses, while double dapples or harlequin dapples may have pink noses. In addition, a piebald dachshund will lose all or almost all of the colour on its body before losing any colour on its face or head. If a dapple dachshund only has colour loss on its face, head, or neck area, then it is likely a double dapple or an extreme harlequin dapple. Harlequin dapples are never safe to breed to other dapples. They should only be bred to dachshunds that are not dapple (mm). 

The chart to the right will determine which types of merle alleles are safe to breed together. Typically, the less severe the dappling, then the safer to breed together.

It is also possible for a dapple dachshund to not have any dappling on the body at all. EE dachshunds, for example, cannot show any amount of dapple. This is because EE removes all black pigment from the body, causing the dachshund's coat to be paler, and the dappling affect only occurs because the merle gene dilutes black pigment on the body. Without any black pigment to dilute, the classic dapple pattern becomes invisible. Not to be confused with hidden dapples, a cryptic dapple (M^c) is when a dachshund is genetically a dapple but can not display any dappling pattern due to a short sine insertion length. A hidden dapple is a typical dapple (M) that does not display any noticable or obvious dappling due to the coat colour or other markings. For example, even strong dappling can be very difficult to see on a light red coat, and therefore, red dapple dachshunds are often hidden dapples. It especially becomes difficult to see dappling on piebald or brindle dachshunds. Because there can be dapple dachshunds with no physical indicators that they are dapple, it is important to always genetic test your dachshunds before breeding them to ensure that you do not accidentally produce an unsafe double dapple. Although, cryptic dapples are considered safe to breed with most other dapples. I always recommend testing with Embark and UC Davis. Embark will determine the alleles of your dachshund and provide other forms of health testing. UC Davis can determine the sine length of a dapple dachshund. A good thing to remember is that if a dachshund has any amount of blue in it's eyes, then it has to be a dapple. However, not all dapples will have blue eyes.

Merle is a dominant gene, meaning that it cannot be carried. One or both parents must be a dapple in order for a dapple to be produced. Dapple should also not be confused with ticking. A dachshund with ticking will have small spots of colour on it. Ticking is not related to dapple. 

Below you will find examples of different types of dapple or non-dapple dachshunds.