Category archives: Trixie's Paw Prints

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 ...

The field of genetics has progressed rapidly in recent years.  Perhaps you’ve seen headlines about these top genetic topics in 2013. These stories show the importance of genetics and how it affects us as individuals and as a society.  To understand the impact, though, one may need a review of Genetics 101: dominant vs. recessive disease traits.

In order for our bodies to work properly, our DNA must be coded in specific sequences.  DNA sequences are grouped into units called genes, which tell our bodies what to make to build cells and metabolize nutrients.  We are all a unique combination of re-shuffled genes from previous generations.  Everything from eye, hair and skin color, muscle, bone, etc. is coded by genes.  A mutation in a gene usually causes something to change and many of these changes can lead to disease. There are thousands of genes, and in humans, thousands of genetic disorders that result from mutations. 

One way to classify genetic disorders is to group them by how they are inherited.  With the exception of the sex chromosomes, X and Y, each of us has two copies of our genes.  One comes from ...

Paw Print Genetics often gets asked about an optimal time to swab a new litter of puppies. When reviewing these tips, please keep in mind that it can take up to two weeks to obtain results once Paw Print Genetics has received the swabs.  Therefore, allow plenty of time for the laboratory to process your samples before promising a specific date that the puppy can join its new home.

Puppies and dogs can be tested at any age. However, it is a good idea to allow the puppies to stabilize after birth, bond with their mother, and demonstrate that they can feed and grow before testing.  You do not have to wait until the puppies are weaned; once the puppies are stable and thriving, they can be swabbed.  For puppies that are not weaned, the puppies should be separated from their mother for at least two hours prior to swabbing. This is to ensure we get the DNA of the puppy instead of the mom's DNA. During this time, they should have plenty of water and should not be allowed food to avoid contamination of samples. Once the swabbing is completed, the pups can rejoin their ...

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 ...

My parents and I were blessed with two healthy, happy apricot Labradoodle puppies in the last year.  Dixie and Liberty were full sisters, 7 months apart, and loved each other with a fervor that I haven’t seen in any of my other animals.  The “sissies” went hiking, shopping at the local feed store, and to costume parties together.  Despite very different personalities, they looked virtually identical and won over the hearts of strangers as they bounced along next to each other on their coupler lead.  They loved to play, run, wrestle, chase the ball, and dig in buckets of water together.  They were inseparable.

On a chilly night in November, the girls were having a regular play date in my fenced city yard.  They were home alone and having the time of their lives.  Dixie jumped toward her little 6-month old sister with an open mouth and the worst happened; her lower canine teeth hooked through Liberty’s nylon collar and the dogs were stuck.  A heart-wrenching struggle ensued.  I pulled into my driveway and rushed to help them.  I was able to get them untwisted, but it was too late ...

Have you ever wondered what goes on in a genetic testing laboratory? What kinds of measures are taken to guarantee quality testing? For example, does the laboratory that you use have what is pictured - a clean room? What is a clean room and why should they have one? And why can’t you bring your dog directly to the laboratory for swabbing?

Paw Print Genetics has received a lot of questions about our testing quality and accuracy – and we love it! Ask away! We like to talk about our lab and the careful approach we take to testing to ensure that your results are reliable and accurate. Otherwise, what’s the point?

A genetic testing lab must have accurate and reliable results. They should have performed validation studies for each of the diseases and mutations that they offer. Does your testing lab provide you with the test’s sensitivity and specificity for the diseases you are concerned about? Have you asked for this?

During our validation studies, we assessed eight performance criteria for each test: accuracy, precision, analytical specificity, analytical sensitivity, detection limits, reportable ranges, reference intervals and robustness. For example, accuracy refers to getting the right results; whereas, precision refers to ...

Rickie Roo is an agility dog, a service dog and a roving reporter for the United States Dog Agility Association. She is well known in the sport of agility and in the rat terrier community. On October 12^th, 2013, Roo unfortunately had to have emergency surgery because of a luxated lens in her left eye. Primary Lens Luxation, or PLL, is a condition that can happen in many breeds including American Eskimo dog, American hairless terrier, Australian cattle dog, border collie, bull terrier, Chinese crested, Jack Russell terrier, jagdterrier, Lakeland terrier, Lancashire heeler, miniature bull terrier, Norwich terrier, Parson Russell terrier, Patterdale terrier, rat terrier, Russell terrier, Sealyham terrier, Teddy Roosevelt terrier, Tenterfield terrier, Tibetan terrier, toy fox terrier, Volpino Italiano, Welsh terrier, wire fox terrier, Yorkshire terrier.

Lens luxation can happen suddenly and when it occurs, needs to be surgically corrected as soon as possible to try to minimize any loss of sight. Luckily, Rickie Roo's luxated lens was caught very early by her owner, Deborah Davidson Harpur. Thanks to early intervention, Rickie ...

Meeting our customers face to face and personally answering their questions is a high priority for Paw Print Genetics. In the last month, several members from our team have hit the road to attend dog shows. We had the pleasure to meet hundreds of dogs and their owners to talk about the value of inherited disease testing when breeding and buying a puppy.

In late September, Casey, our DVM and Assistant Medical Director and I travelled to Salem, Oregon for The Poodle Club of America’s Regional Specialty. We met poodles of all sizes and colors from all over the region. The poodle owners spent hours grooming and attending to their canines, but when they had a moment they stopped by our booth to talk about their concerns regarding genetic diseases.  Our Poodle Panel  includes six inherited diseases found in the breed. After discussing health concerns with these owners, most indicated that they always test for PRA-PRCD and neonatal encephalopathy. Many people were unaware that several breeds, including poodles, are possible carriers for degenerative myelopathy, a devastating disease with onset later in life.

Before returning to Spokane, we had one more show to attend in Kennewick, Washington for the 80 ...