Bella's Eye Defect .....Coloboma!

Coloboma is an eye abnormality that occurs before birth. Colobomas are missing pieces of tissue in structures that form the eye. 

Colobomas affecting the iris, which result in a "keyhole" appearance of the pupil, generally do not lead to vision loss.

People with coloboma may also have other eye abnormalities, including clouding of the lens of the eye (cataract), increased pressure inside the eye (glaucoma) that can damage the optic nerve, vision problems such as nearsightedness (myopia), involuntary back-and-forth eye movements (nystagmus), or separation of the retina from the back of the eye (retinal detachment).

Some individuals have coloboma as part of a syndrome that affects other organs and tissues in the body. These forms of the condition are described as syndromic. 

Coloboma occurs in approximately 1 in 10,000 people.

Coloboma arises from abnormal development of the eye. During the second month of development before birth, a seam called the optic fissure (also known as the choroidal fissure or embryonic fissure) closes to form the structures of the eye. When the optic fissure does not close completely, the result is a coloboma. The location of the coloboma depends on the part of the optic fissure that failed to close.

Coloboma may be caused by changes in many genes involved in the early development of the eye, most of which have not been identified. The condition may also result from a chromosomal abnormality affecting one or more genes.

You can see in this photo an example of Coloboma best seen in light colored eyes. This shows you an eye with coloboma compared to a normal eye.

Bella's eyes have coloboma in both eyes and in this next photo it is am example that will show where they are in her eyes, they run the opposite directions towards her nose.  This is not her eye.

Genes that can be affected: And need to be tested for.....

The GDF3 gene is known to be involved in bone and cartilage development

 GDF6 protein is necessary for the formation of bones and joints in the limbs, skull, spine, chest, and ribs. The protein is involved in setting up boundaries between bones during skeletal development.

The OTX2 gene plays a critical role in the development of the eyes and related structures, such as the nerves that carry visual information from the eyes to the brain (optic nerves). 

During embryonic development, the PAX6 protein is thought to activate genes involved in the formation of the eyes, brain and spinal cord (central nervous system), and the pancreas.

SHH gene, Sonic Hedgehog plays a role in cell growth, cell specialization, and the normal shaping (patterning) of the body.

The MAF gene and VSX2 gene are the last two but are very complex in description.

They want to determine that she does or does not have :

WAGR syndrome is a rare genetic syndrome in which affected children are predisposed to develop Wilms tumour (a tumour of the kidneys), Aniridia (absence of the coloured part of the eye, the iris), Genitourinary anomalies, and mental Retardation. The G is sometimes instead given as "gonadoblastoma," since the genitourinary anomalies are tumours of the gonads (testes or ovaries).

WAGR syndrome is caused by a mutation on chromosome 11 in the 11p13 region.Specifically, several genes in this area are deleted, including the PAX6 ocular development gene and the Wilms' tumour gene (WT1). Abnormalities in WT1 may also cause genitourinary anomalies. Mutations in the PAX6 gene have recently been shown to not only cause ocular abnormalities, but also problems in the brain and pancreas.

Children with WAGR syndrome receive regular (3-4 monthly) kidney surveillance for Wilm's tumour until at least the age of 6–8 years and thereafter remain under some follow-up because of the risk of late onset nephropathy (40% of patients over the age of 12 years). Females with WAGR syndrome may have streak ovaries, which can increase their risk for gonadoblastoma. Malformations of the vagina and/or uterus may also be present.

We will  be going to have her genealogical DNA testing done as soon as we can get in as a new patient.