Putting our heads together: Canines may hold clues to human skull development

Feb 08, 2013

Man's best friend may touch our hearts with their empathy, companionship, playfulness and loyalty, and they may also lead us to a deeper understanding of our heads.

In the article, "The Genetics of Canine Skull Shape Variation," in the February issue of the Genetics Society of America's journal, Genetics, Jeffrey J. Schoenebeck, PhD, and Elaine A. Ostrander, PhD, researchers at the National Institute (NHGRI), the National Institutes of Health (NIH), review progress in defining the genes and pathways that determine canine skull shape and development that have been made in the eight years since the dog genome was mapped.

The implications of this research extend beyond the interests of dog fanciers and breeders. "Dogs can serve as a model for skull growth and shape determination because the genetic conservation between dogs and humans makes it highly likely that craniofacial development is regulated similarly between both species," Dr. Schoenebeck said. "These discoveries are important for human health and biology, especially for children born with craniofacial deformities," Dr. Ostrander, added. In humans these deformities include Apert, Crouzon and Pfeiffer syndromes, where skull bones fuse prematurely causing , such as wide-set bulging eyes and broad foreheads, resulting in dental, eye and other physiological problems.

Skull shape is a complex trait, involving multiple genes and their interactions. Thanks to standardized canine breeding, which documents more than 400 breeds worldwide, and their distinct morphological features, researchers can disentangle traits such as , which in many breeds is a breed-defining variation.

For example, researchers are beginning to identify which genes cause a Bulldog or a Pug to have short pushed-in faces, or brachycephaly, and those that cause Saluki's or collies to have narrow, elongated snouts, or dolichocephaly. Between these two distinct canine cranium shapes are many variations that are also breed specific but can't be neatly categorized as brachycephalic or dolichocephalic, such as the rounded skull of the Chihuahua or the downward pointing snout of the Bull terrier. Researchers now use genome-wide association studies (GWAS) to identify loci of interest that may be associated with these kinds of subtle differences.

The use of GWAS in determining genetic variation in dogs is in its infancy. What's exciting said Dr. Schoenebeck is that with these studies and the tools researchers now have to map these variations "we may find new roles for genes, never before implicated in cranium development" and because similar genes and genetic pathways operate in humans, unexplained craniofacial developmental defects may become better understood.

Identifying the causative genetic mechanisms of these variations in canines offer researchers who study human cranial abnormalities "a way to figure out what sort of genetic variation matters and what doesn't," said Dr. Ostrander.

Drs. Schoenbeck and Ostrander clearly show there's a lot more research to do on craniofacial development in dogs. It is also clear that the connection between us and our canine friends is in our heads as well as our hearts.

Explore further: New insights into how different tissues establish their biological and functional identities

More information: Schoenebeck, Jeffrey J. and Elaine A. Ostrander, The genetics of canine skull shape variation, Genetics, February 2013 193:317-325

add to favorites email to friend print save as pdf

Related Stories

Canine morphology: Hunting for genes and tracking mutations

Mar 02, 2010

Why do domestic dogs vary so much in size, shape, coat texture, color and patterning? Study of the dog genome has reached a point where the molecular mechanisms governing such variation across mammalian species are becoming ...

Dog brains in a spin

Jul 28, 2010

For the first time, scientists have shown that selective breeding of domestic dogs is not only dramatically changing the way animals look but is also driving major changes in the canine brain.

Recommended for you

Deadly human pathogen Cryptococcus fully sequenced

22 hours ago

Within each strand of DNA lies the blueprint for building an organism, along with the keys to its evolution and survival. These genetic instructions can give valuable insight into why pathogens like Cryptococcus ne ...

User comments : 0

More news stories

Plants with dormant seeds give rise to more species

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

Researchers develop new model of cellular movement

(Phys.org) —Cell movement plays an important role in a host of biological functions from embryonic development to repairing wounded tissue. It also enables cancer cells to break free from their sites of ...

Male monkey filmed caring for dying mate (w/ Video)

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

LinkedIn membership hits 300 million

The career-focused social network LinkedIn announced Friday it has 300 million members, with more than half the total outside the United States.

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

Sun emits a mid-level solar flare

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...