2017 July August

Q&A
Do These Genes Fit?
How do Aussie cancer statistics compare
to those of other breeds? And how do we
know if cancers are inherited?
Your statistical question isn’t easy to
answer. I’m familiar with some Aussie
statistics through my work with ASHGI,
but I don’t have ready access to similar data
on other breeds. That said, it is generally
known among cancer researchers and
veterinarians that dogs, like people, are
cancer-prone. Cancer is a common cause
of death, especially in old age, for both
species. ASHGI did a survey of Aussies
with cancer about ten years ago. 26.4% of
the dogs with cancer were reported to have
hemangiosarcoma (HSA) and 23% to have
lymphoma/lymphosarcoma (alternate
names for the same disease). If you factor
in dogs for whom the respondent indicated
cancer location rather than cancer type,
those with typical sites for HSA tumors
constituted up to 23.4% which were
probable HSA cases, possibly making that
cancer responsible for about half of the
cases I the breed.
When certain cancers predominate or
occur with above-average frequency in a
particular breed or there are cancers that
clearly follow family lines, those cancers
almost certainly have an inherited risk.
Both of these are the case with Lymphoma
and HSA in Aussies as they are in several
other breeds including Goldens and
Salukis.
In ASHGI’s 2009-10 general health
survey 5% of dogs were reported to have
had hemangio and 2% lymphoma, a
proportion roughly equivalent to the earlier
findings from dogs with cancer. It also
indicates that about one Aussie in 14 will
get one of these two cancers. All other
cancers appear to be spontaneous in the
breed.
If you want to do some data-mining
from our surveys, the reports and pdfs with
70 AUSSIE TIMES May-June 2017
Send your questions to:
C.A. Sharp
1338 Trouville Ave.
Grover Beach, CA 93433
ph. 805-473-0078
e-mail: 51ca@ashgi.org
summary data can be found here: http://
www.ashgi.org/home-page/genetics-info/
health-surveys
My red merle girl has a lot of white and is
lighter than some so I’m wondering if she
could be dilute? Should I get a color test
panel done?
The amount of white markings has
nothing to do with dilute.
There is a wide range of pigmentation
in reds that are not dilute. True dilutes can
be difficult to distinguish from reds that are
lighter for other reasons, especially the
merles. DNA testing could tell you whether
or not she is dilute but you don’t need a full
color panel to do this. All you need is the
dilute test, often called “D-locus” or
“MLPH” (the name of the gene.) If she has
two recessive copies of that gene then she
is dilute.
I’m considering a frozen semen
insemination using semen collected in
1992. I have been informed that a DNA
profile can be established on frozen
material. Can DNA health testing be
obtained with the same lab/same time? I
was told the breed club would take care of
this.
I’m not sure why someone said a breed
clubs could do this for you. ASCA does
have its own DNA profiling/parentage
verification program. I’m not aware of any
breed club that operates it’s own a DNA
health testing program, though some may
have a member benefit that offers a discount
as ASCA does with Paw Print Genetics.
Given that the dog is long gone you’ll
need to sacrifice some of the stored semen
for testing, with separate samples for the
DNA profile and health testing. ASCA’s
DNA program will accept semen as a
sample but you need to make arrangement
with the office prior to submitting it. Since
your dog was collected before January 1,
1999 ASCA doesn’t require a DNA profile
though you may want to check with the
office to see if there is anything you need
to do to verify date of collection and whose
semen it was when you register the litter.
For health testing you should canvas
DNA health testing labs you’d like to use
to see if they will accept a semen sample.
It might require special handling which
they may or may not be able to accommodate
or may charge an additional fee. When you
find a lab be sure to discuss shipping
requirements (do they need it to stay frozen,
etc.)
The tests I would most recommend are
MDR1 and HSF4 (cataracts) plus anything
you know that your bitch carries.
A friend of mine’s dog was diagnosed with
idiopathic epilepsy. The breeder really
bashed her on her Facebook page and said
idiopathic means they don’t know what
causes that so it isn’t genetic. He said it’s
a relatively new thing in Aussies and years
ago you never heard of it.
I beg to differ on several counts. The
term “idiopathic” was hung on the disease
years ago before there was a good
understanding of the genetics involved.
Today the cause and it is known: Genes.
Researchers wouldn’t be spending time and
money on canine epilepsy genetic research
if this were a big question mark.
Once a dog has been diagnosed with
idiopathic (also called primary or inherited)
epilepsy, those who have the affected dog