|
 |
-represent
genetic
: NORMAL |
|
 |
-represent
genetic
:
CARRIER |
|
 |
-represent
genetic
:
AFFECTED |
|
|
|
These are only six possibilities for
mating.
Each of our dogs is the product of one of
these six
breeding
combinations.
Both
GM-1* and PRA, Progressive Retinal Atrophy,
are recessive
genes.
This
chart can be applied to the
genetic
inheritance pattern
of each disease.
|
|
|
_________________________________________________________________________________________________________________
EXPECTED
AVERAGE RESULT, BASED ON A
MINIMUM OF 16 PUPPIES
|
|
PARENTS
|
OFFSPRING
|
|
|
 |
Both parents are NORMAL, not
carrying the recessive gene.
100
% of the puppies will be
NORMAL.
|
|
_________________________________________________________________________________________________________________ |
|
PARENTS
|
OFFSPRING
|
|
|
 |
One
parent is NORMAL, one parent
is CARRIER of the recessive
gene ... 50 % of the
offspring will be NORMAL, 50
% will be
CARRIERS.
In
"Storage" disease Carriers
can be detected by a blood
assay.
In PRA, Carriers can not be
detected that easily thus
pedigree
analysis
is critical
|
|
_________________________________________________________________________________________________________________ |
|
PARENTS
|
OFFSPRING
|
|
|
 |
An
AFFECTED parent will always
produce CARRIER offspring.
In
this situation, only 50 % of
the offspring will be
AFFECTED,
but
the other 50 % will still be
CARRIERS.
AFFECTED individuals used
for breeding automatically
identify
their offspring's as
CARRIERS.
|
|
_________________________________________________________________________________________________________________ |
|
PARENTS
|
OFFSPRING
|
|
|
 |
CARRIER to CARRIER breedings
will produce 25 % AFFECTED
offspring ; 25 % NORMAL
offspring ; and 50 %
CARRIERS.
In
"Storage" disease, the
process of genetic
identification has
been simplified for us. In
PRA, the identification of
the
different
offspring's genetic make-up
is extremely complex.
|
|
_________________________________________________________________________________________________________________ |
|
PARENTS
|
OFFSPRING
|
|
|
 |
An
AFFECTED parent will always
produce 100 % CARRIER
offspring.
AFFECTED parent breed to
NORMAL parent will not
produce
any
AFFECTED offspring, but they
will all be CARRIERS.
|
|
_________________________________________________________________________________________________________________ |
|
PARENTS
|
OFFSPRING
|
|
|
 |
AFFECTED parent bred to
AFFECTED parent will always
produce all AFFECTED
offspring.
|
|
|
