Tag archives: dog genetic testing

In the world of human genetics, stories related to hereditary cancer predisposition syndromes have recently made quite a splash in the media.  For example, actress Angelina Jolie made a very public decision to have a double mastectomy in order to reduce her breast cancer risk.  There are other popular stories as well.  Although hereditary cancer predisposition syndromes are not as common in the canine population as they are in the human population, knowing a little information about these genetic conditions and how they work may impact breeding practices. 

What exactly is a hereditary cancer predisposition syndrome?  Those are a lot of complicated words.  Let’s dissect that phrase: 

                  Hereditary – inherited, genetic, passed from parent to offspring. 

                  Cancer – uncontrolled invasive abnormal cell growth. 

                  Predisposition – tendency towards or gravitation to. 

                  Syndrome – a group of symptoms with a single cause.

A hereditary cancer predisposition syndrome gives the affected individual a tendency to develop cancer.  Cancer, for the most part, is multifactorial.  That means there are genetic and environmental influences.  However, hereditary cancer predisposition syndromes have a much greater genetic influence than environmental influence ...

My last two articles on dominant and recessive inheritance and X-linked inheritance have built upon each other and discussed different types of inheritance: dominant, recessive and X-linked.  These three modes of genetic transmission are fairly straightforward compared with the topic of today’s post, which is mitochondrial inheritance.  Maybe you’ve never heard of the word “mitochondria” before.  Or perhaps just reading the word brings you back to high school cell biology.  While this may be a rare form of inheritance, diagnosing a dog with a mitochondrial disorder may impact how breeders choose to breed their animals.

Before we discuss the mitochondrial inheritance, let’s talk about mitochondria. Just like our bodies need organs to function (kidneys, heart, liver, etc.), cells have organelles too.  One of the organelles is called a mitochondrion or mitochondria (plural).  Mitochondria are the energy powerhouses of the cell.  They create energy through a series of biochemical reactions.  The number of mitochondria can change depending on the type of cell (muscle, nerve, skin, etc.). 

The neat thing about mitochondria is that they have their own set of DNA, called mtDNA, separate from the DNA found in the nucleus; mtDNA is ...

The pointing Labrador is just one of many exceptional dog breeds. Versatile in their ability to point, flush and retrieve, pointing Labradors may be the perfect hunting companion.  How a specific dog breed has so many desirable characteristics is not a mystery. All domesticated dogs were bred for specific behavioral or physical traits that were required for certain jobs – whether it was for chasing and catching varmints, retrieving the evening’s dinner, or bringing in the herd, dogs are the perfect species for a variety of tasks.  

All of these traits, behavioral and physical, have a genetic component and are determined by an accumulation of genes with modifications, or mutations, that result in some outcome. Whether the traits are pointing, coat color or skull structure, humans chose founding stock to create the various breeds and bred these dogs for the traits they desired.  However, undesirable, even harmful genetic mutations were carried along in these breeds. The most ancient mutations can be found in many breeds of dogs, whereas those mutations that arose more recently maybe found in only one or two breeds.

With the advent of molecular genetic technologies and the sequencing of the domestic dog (Canis ...

My last blog talked about the basics of two types of inheritance for genetic conditions found in dogs: dominant and recessive.  To review, dominant conditions need one copy of the mutated gene in order for the dog to show symptoms.  Recessive conditions need both copies of the mutated gene inherited from each parent to have the disease.  Knowing the difference can change the way breeders choose which dogs to breed.  However, the wonderful world of genetics is not that simple.  Another pattern of inheritance is called X-linked, or sex-linked.  Although it is not as common as dominant and recessive; it is important to know which diseases follow this inheritance pattern, because it may impact breeding.

Dogs have 39 pairs of chromosomes (humans have 23).  Something dogs and humans have in common is the X and Y chromosomes determine gender.  XX is a female while XY is a male.  Females always give away an X chromosome to their offspring.  So, it is the male that determines gender for the next generation.  If he passes on the X chromosome, the offspring is female.  If he passes on the Y chromosome ...

One of the best compliments that a company can receive is when a customer places another order after experiencing that company’s service. An even better compliment is when a customer refers that business to a friend or colleague. When we refer a friend to a business, we are putting our ‘stamp of approval’ on that business and putting our reputation on the line too. We hope that the company will provide that excellent customer service every time so that our friend doesn’t blame us if things go wrong. That is why referrals are so valuable to a company and why excellent customer service should be every company’s number one priority.

What constitutes excellent customer service? This may include an informative and easy to use website interface, a friendly human voice when the company answers the phone, the outstanding quality of the service they provide, and its caring interactions with the customer long after the service has been completed. When was the last time you ordered something and didn’t receive an email confirmation or reply that your precious purchase was on its way? The communication that a company has with its customer says a lot about the way it conducts its ...

On April 30th, you will be able to order genetic testing for your dogs from Paw Print Genetics^TM. Before we could open our doors for clinical testing, we had a lot of work to do, work that involved my entire family and our extraordinary staff.  We had to build an entire laboratory from the ground up. Part of that process was validating our tests, which, as I’ll explain, is an important and necessary step – and one that involved many of you. 

After more than 20 years of working in human genetic diagnostic testing, I decided to use these skills to improve genetic testing for inherited canine diseases. We are so grateful for the support of the community of dog owners and breeders who participated in our validation studies from December 2012 through March 2013. As unknowns in this industry, we appreciate your trust that we were doing the right thing with your dog’s DNA.

We set up our laboratory, designed our tests and conducted our validation as if Paw Print Genetics were a human diagnostic laboratory. This means that we have all of the validation documentation that would be required if we were regulated by ...

Continuing the series on "when genes don't make sense," let’s talk about probabilities. Many people will hear that if a condition is recessive that one in four puppies will be affected or, if it is dominant, that 50% of the puppies will exhibit the trait or be affected with a condition. They will subsequently declare that because the outcome in their litter is different than these exact percentages, it therefore must not be… recessive, dominant or genetic at all.

On the other hand, many people in dogs will say things like "they need to breed a male in order to determine if he produces males or females."

These are different errors in reasoning relating to the same type of probability.

In the first case, people are expecting the actual results to be exactly what is predicted based on possible results or probabilities. In the second case, people are assigning meaning to the random variation that is usually observed (and actually expected) compared to what is predicted based on probability.

To start with the second scenario, millions of sperm are swimming as hard as they can to fertilize the eggs. Roughly 50% of these sperm carry an X chromosome ...