In contrast, an autosomal
dominant mode of inheritance with a high degree of penetrance has been suggested for the pulverulent (dust - like) form of cataract observed in the Norwegian Buhund [116] and autosomal dominant with variable penetrance has been suggested for inherited posterior polar subcapsular cataracts in the Labrador and Golden retriever [117], although current anecdotal evidence indicates that in the Labrador cataracts could also be inherited as an autosomal recessive trait.
The abundance of carriers in the population caused initial difficulties in characterizing the mode of inheritance with certainty and it was suspected that the disease had an autosomal
dominant mode of inheritance.
A simple
dominant mode of inheritance can be excluded because the vast majority of affected dogs were born to clinically normal parents.
Further research by Dr. Nicholas Dodman into the genetics suggests
a dominant mode of inheritance for this condition.
Not exact matches
To the contrary, our normal experience has a focused center washed over by a series
of vaguely discriminated backgrounds, any one
of which can snap to the center
of attention given appropriate stimuli, and I hold that it is my model
of dominant and oblique
inheritance and not his model
of regionally inclusive
inheritance which most adequately reflects this normal
mode of awareness.
The
mode of inheritance for most Aussie cataracts is
dominant with incomplete penetrance, meaning not every dog with the mutation will develop cataracts though 70 %
of those with cataracts have it.
Discovery
of genetic links and
of the
mode of inheritance (simple or complex,
dominant or recessive) is the work
of researchers, but they must have dogs to study.
The
mode of inheritance has not been determined precisely but the fact that dogs heterozygous for the KRT71 mutation do not have curls and also the occasional occurrence
of dogs with curly hair in breeds with typically straight hair suggests that the curly hair is inherited in a recessive or incompletely
dominant mode.
In contrast, the form
of cataract observed in the Australian Shepherd, caused by the deletion described above, has a
dominant, or co-
dominant mode of inheritance, is not completely penetrant and is typically associated with a posterior polar subcapsular cataract that also has a variable age
of onset.
The
mode of inheritance is unclear, however appears that it may be a
dominant trait.
In our study
of primary epilepsy, in English Springer Spaniels, Vizslas, and research Beagles the first step will be to determine the
mode of inheritance for each breed (simple recessive, simple
dominant, sex - linked, or polygenic).
Depending on the particular variety, the
mode of inheritance could be autosomal recessive or
dominant, or X-chromosome-linked recessive or
dominant, some with full penetrance, and some not.