I felt Timothy needed his own post....
Someone asked me about Timothy and why are kids born without eyes....so in case anyone else was wondering.....
Here are some answers thanks to Wikipedia!
Anophthalmia, (Greek: ανόφθαλμος, "without eye"), is the medical term for the absence of one or both eyes. Both the globe (human eye) and the ocular tissue are missing from the orbit.[1] The absence of the eye will cause a small bony orbit, a constricted mucosal socket, short eyelids, reduced palpebral fissure and malar prominence.[2] Genetic mutations, chromosomal abnormalities, and prenatal environment can all cause anophthalmia. Anophthalmia is an extremely rare disease and is mostly rooted in genetic abnormalities. It can also be associated with other syndromes
Epidemiology
Anophthalmia has been reported to be present in 3 out of every 100,000 births.[3] Many instances of anophthalmia also occur with microphthalmia. A recent study in England indicated that anophthalmia and microphthalmia had a combined average of 1 in every 10,000 births.[1] The annual rate of occurrence of anophthalmia/microphthalmia in the United States is about 780 children born/year.[4] Parents that already have a child who suffers from anophthalmia has a 1 in 8 chance of having another child with anophthalmia.[5] Approximately 2/3 of all cases of anophthalmia are determined to be of genetic basis. Anophthalmia is one of the leading causes of congenital blindness and accounts for 3-11% of blindness in children.[6] Anophthalmia and microphthalmia together make up 1.7-1.8% of reconstructive surgical cases in laboratory of plastic surgery and ocular prostheses.[7]Causes
Sox2 gene
The most genetic based cause for anophthalmia is caused by the SOX2 gene. Sox2 anophthalmia syndrome is caused by a mutation in the Sox2 gene that does not allow it to produce the Sox2 protein that regulates the activity of other genes by binding to certain regions of DNA. Without this Sox2 protein, the activity of genes that is important for the development of the eye is disrupted. Sox2 anophthalmia syndrome is an autosomal dominant inheritance, but the majority of patients who suffer from Sox2 anophthalmia are the first in their family history to have this mutation. In certain cases, one parent will possess the mutated gene only in their egg or sperm cell and the offspring will inherit it through that. This is called germline mosaicism.[8] There are at least 33 mutations in the Sox2 gene that have been known to cause anophthalmia. Some of these gene mutations will cause the Sox2 protein not to be formed, while other mutations will yield a non-functional version of this protein.Other influential genes
Sox2 is not the only gene that can cause anophthalmia. Other important genes include OTX2, CHX10 and RAX. Each of these genes are an important in retinal expression. Mutations in these genes can cause a failure of retinal differentiation.[3] OTX2 is dominantly inherited. Mutation effects vary in severity, and can include microphthalmia. BMP4 is also linked to anophthalmia, as well as causing myopia and microphthalmia. It dominantly inherited. BMP4 interacts with the Sonic Hedgehog pathway and can cause anophthalmia.[9]Environmental influence
Many environmental conditions have also been known to cause anophthalmia. The strongest support for environmental causes has been studies where children have had gestational-acquired infections. These infections are typically viral. A few known viruses that can cause anophthalmia are toxoplasmosis, rubella, and certain strands of the influenza virus.[10] Other known environmental conditions that have led to anophthalmia are maternal vitamin A deficiency, exposure to X-rays during gestation, solvent abuse, and exposure to thalidomideChromosome 14
An interstitial deletion of chromosome 14 has been known to occasionally be the source of anophthalmia. The deletion of this region of chromosome has also been associated with patients having a small tongue, and high arched palate, developmental and growth retardation, undescended testes with a micropenis, and hypothyroidism. The region that has been deleted is region q22.1-q22.3. This confirms that region 22 on chromosome 14 influences the development of the eye.[11]Classifications
There are three classifications for this condition:- Primary anophthalmia is a complete absence of eye tissue due to a failure of the part of the brain that forms the eye.
- Secondary anophthalmia the eye starts to develop and for some reason stops, leaving the infant with only residual eye tissue or extremely small eyes which can only be seen under close examination.
- Degenerative anophthalmia the eye started to form and, for some reason, degenerated. One reason for this occurring could be a lack of blood supply to the eye
-------------------------------------------------------------------------------------------------------------------------
Timothy has no mental delays, he speaks English and Chinese fluently....that is more that I can do!!!!!!!
He does have some CP.
Sarah only had one eye that developed.....
-----------------------------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Both Sam and Sarah have Peter's Anomaly and that is why their eyes were affected....
----------------------------------------------------------------------------------------------------------------------------
I'm praying to get an email from someone who is looking for a wonderful son......Timothy needs a family.....please pray!!!
Is he Chinese, Yvonne?
ReplyDeleteThanks for addressing and answering my questions about the lack of eyes. I pray that he finds a family soon.
ReplyDelete