Dec. 7, 2005 – The embargoed news release below, issued by Cold Spring Harbor Laboratory Press, is about the new issue of the journal Genome Research, and a new book, “The Dog and Its Genome.”
Karl Gordon Lark — a distinguished professor emeritus of biology at the University of Utah — is the principal author of two papers scheduled to appear Dec. 8, 2005, in Genome Research and three chapters in “The Dog and Its Genome.”
For reporters interested in contacting Lark for a story on his research, he may be reached at his office (801) 581-7364, his cellular phone (801) 599-6770 or by email at firstname.lastname@example.org
Three paragraphs in the news release below summarize Lark’s two studies in Genome Research. They are under the heading “Sizing up skeletal variation .”
Lark says one of his book chapters summarizes his research team’s years of work on the genetics of Portugese water dogs, while another chapter, written in collaboration with Russian scientists, deals with research on foxes, which are ancestors of dogs.
Web sites providing background on Lark’s research may be found at:
Copies of the two Genome Research studies are available from me on request by email.
Lark’s book chapters are as follows:
— Genetic Analysis of the Canid Skeleton: Morphological Loci in the Portuguese Water Dog Population by K.G. Lark, K. Chase, D.R. Carrier, and F.R. Adler (all authors are from the U of Utah)
— Morphology and Behavior: Are They Coupled at the Genome Level? by L.N. Trut, A.V. Kharlamova, A.V. Kukekova, G.M. Acland, D.R. Carrier, K. Chase, and K.G. Lark (D.R. Carrier, K.Chase, and K.G. Lark are all from the U of Utah)
— The Genetics of Domesticated Behavior in Canids: What Can Dogs and Silver Foxes Tell Us about Each Other? by A.V. Kukekova, G.M. Acland, I.N. Oskina, A.V. Kharlamova, L.N. Trut, K. Chase, K.G. Lark, H.N. Erb, and G.D. Aguirre (K. Chase and K.G. Lark are both from the U of Utah)
Here are the full names and contact information for the additional University of Utah coauthors listed above:
— David R. Carrier is a professor of biology, (801) 585-7967, email@example.com
— Kevin Chase is research associate in biology, (801) 581-5416, firstname.lastname@example.org
— Frederick R. Adler is a professor of biology and mathematics, (801) 585-6202, email@example.com
Carrier and Chase are Lark’s co-authors on the Genome Research study on the genetics of skeletal variation in dogs, mentioned in the news release below.
Chase, Carrier and Adler are Lark’s University of Utah co-authors on the Genome Research study dealing with sexual dimorphism in dogs — the size difference between males and females.
Lee Siegel, science news specialist
University of Utah Public Relations
Scientists fetch useful information from dog genome publications
Thursday, Dec. 8, 2005 – Today a plethora of dog genome-related materials are published, including a new book titled “The Dog and Its Genome” and a series of primary research articles in the journal Genome Research. These publications, concomitant with the publication by Nature of a high-quality draft sequence of the dog genome, are expected to provide both researchers and the public with informative resources about canine genomics and biology.
“Canine genetics has entered a period of unprecedented growth and discovery,” explain Drs. Elaine Ostrander and Francis Galibert in their Foreword to “The Dog and Its Genome.” “The dog is now set to take its rightful place as a valued system for genetic studies along with the mouse, rat, and several insect species.”
Phenotypic variation among dog breeds, whether it be in size, shape, or behavior, is greater than for any other animal. Because of this diversity, the dog has attracted enormous interest as a model organism for genome plasticity. In addition, dogs are susceptible to genetic diseases that are difficult to study in humans, including cancer, blindness, heart disease, deafness, autoimmune disorders, and neurological diseases, making the dog model system particularly useful in medical and pharmaceutical research.
“The Dog and Its Genome” puts these and other aspects of the dog into context and focus. In the book’s 26 chapters, dog experts cover morphological and behavioral variation in dogs, their origins and domestication, and characteristics of their genome. Chapters are devoted to discussing the genetic basis of canine diseases, as well as health initiatives aimed at curing diseases in dogs by approaches that include genetic testing and gene therapy. The book also deals with the history of dog breeds, the American Kennel Club, dog shows, and dogs as helpers.
How canine chromosomes crumble
In a special dog genome section of the journal Genome Research, University of Oxford researchers Dr. Caleb Webber and Prof. Chris Ponting are publishing a manuscript describing their comparison of dog and human chromosomes. Since the evolutionary divergence of dogs and humans approximately 95 million years ago, canine chromosomes have undergone considerable breakage relative to other species. In contrast to the 46 chromosomes present in each human cell, dogs possess 78 chromosomes, but each set essentially encode the same amount of information.
“We present a new model of chromosome evolution that accounts for the extensive breakage seen in the dog genome,” explains Webber. “Our results demonstrate that dog chromosomes have not broken randomly, which is the commonly held view, but instead that they preferentially fracture within ancient ‘hot spots.’ These fragile ‘hot spots’ contain an unusual number of guanine and cytosine DNA bases and appear to suffer higher rates of mutation.”
SINEs of genetic diversity
Another study appearing in the dog genome section of Genome Research highlights an important source of canine genomic variation: SINEs, or short interspersed elements. SINEs are abundant mobile DNA elements that are common in mammals and have contributed extensively to genome evolution. In their publication, Drs. Wei Wang and Ewen Kirkness, scientists at The Institute for Genomic Research, report the identification of more than 10,000 SINE insertions in the canine genome and describe the potential impact of these insertions on phenotypic diversity in dogs.
“These SINEs are bimorphic, which means that at a given locus, some dogs have the SINE sequence while others do not,” explains Kirkness. “This may have a profound impact on gene expression differences and disease determination in dogs.”
SINE-associated diseases have already been described in Doberman Pinchers and Labrador Retrievers. For example, centronuclear myopathy, a muscle-wasting disease, is associated with a SINE insertion in a gene called PLPTA. The discovery of highly variable patterns of SINE insertion between individual dogs suggests that SINEs may play a significant role in canine disease and diversity.
Sizing up skeletal variation
Portuguese Water Dogs (PWDs) were originally derived from two kennels that disagreed on an appropriate size standard for the breed. Although there were only a few animals in this initial gene pool, the considerable size differences among the founding individuals has made the PWD breed an excellent model for investigating the genetic basis of skeletal variation. Dr. Gordon Lark, Distinguished Professor Emeritus of Biology at the University of Utah, has been studying skeletal variation in the PWD breed and is the principal investigator on two papers appearing in the dog section of Genome Research.
In one of the publications, Lark’s group reports forty QTL, or quantitative trait loci, that are responsible for determining skeletal size in dogs. A striking aspect of these loci is that they control functionally related skeletal traits. “For example,” says Lark, “one of the QTL that we identified controls both pelvic size and metacarpal length, but the two traits are inversely correlated. This could represent a functional trade-off between high-speed, energy efficient running versus limb strength. Mammals specialized for running tend to exhibit large pelvic bones and relatively slender limbs.”
In the second manuscript, Lark’s team describes the genetic basis for sexual dimorphism, or size differences between male and female dogs. They attribute the differences to at least two interacting loci, one of which is located on the X chromosome. “Sexual dimorphism seems to have evolved as females became smaller than males due to natural selection for optimal size,” Lark explains. “This is consistent with our finding that a variant on the X chromosome plays a role in skeletal size determination.”
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“The Dog and Its Genome”
Edited by Elaine A. Ostrander, Urs Giger, and Kerstin Lindblad-Toh © 2006 Cold Spring Harbor Laboratory Press 584 pp., illus., index; ISBN 0-87969-742-3
For more information or to order The Dog and Its Genome, visit www.cshlpress.com. Cold Spring Harbor Laboratory Press is an internationally renowned publisher of books, journals, and electronic media, located on Long Island, New York. It is a division of Cold Spring Harbor Laboratory, an innovator in life science research and the education of scientists, students, and the public.
Please direct requests for copies of the dog-related Genome Research manuscripts to Maria Smit, Assistant Editor (firstname.lastname@example.org). Genome Research (www.genome.org) is an international, monthly, peer-reviewed journal published by Cold Spring Harbor Laboratory Press. Launched in 1995, it is one of the five most highly cited primary research journals in genetics and genomics.
The following investigators, who are lead authors on the Genome Research manuscripts mentioned above, have agreed to be contacted regarding their dog genome research:
Ewen Kirkness, Ph.D.
Department of Mammalian Genomics, The Institute for Genomic Research
K. Gordon Lark, Ph.D.
Department of Biology, University of Utah
Caleb Webber, Ph.D.
MRC Functional Genetics Unit, University of Oxford