Besides skeletal indications, there are eye disorders such
as microphthalmia (smaller eyes than they should be), lens detachments, cataracts, glaucoma, retinal defects, and nystagmus (jerking or twitching of the eyeballs).
Damage to human chromosome 9 (of the cell's 24 pairs) where the gene that codes for E-NTPDase2 resides is known to cause eye and brain defects, such
as microphthalmia — literally, small eyes.
Not exact matches
This form of
microphthalmia is inherited
as an autosomal recessive trait in some breeds.
Other double merles suffer from
microphthalmia, where the eye is smaller than normal, in some cases it appears
as if there is no eye at all (anophthalmia).
A recessive mode of inheritance has been suggested for congenital cataracts and
microphthalmia in the Miniature Schnauzer [112]
as well
as cataracts in the Entlebucher mountain dog [113], the Bichon Frise [114] and the American Cocker spaniel [115].
Examples of the latter might include: choroidal hypoplasia in breeds not previously identified
as having Collie Eye Anomaly, optic nerve colobomas,
microphthalmia, multi-focal retinopathy in breeds not yet recognized
as having CMR mutations, etc..