Lending credibility to this has been the discovery of disease-associated genetic polymorphisms in other elements of the complement cascade including complement component 3 (C3).A powerful predictor of AMD is found on chromosome 10q26 at LOC 387715. An insertion/deletion polymorphism at this site reduces expression of the ARMS2 gene though destabilization of its mRNA through deletion of the polyadenylation signal. ARMS2 protein may localize to the mitochondria and participate in energy metabolism, though much remains to be discovered about its function. Other gene markers of progression risk includes tissue inhibitor of metalloproteinase 3 (TIMP3), suggesting a role for extracellular matrix metabolism in AMD progression. Variations in cholesterol metabolising genes such as the hepatic lipase, cholesterol ester transferase, lipoprotein lipase and the ATP-binding cassette A1 correlate with disease progression. The early stigmata of disease, drusen, are rich in cholesterol, offering face validity to the results of genome-wide association studies. Stages
In AMD there is a progressive accumulation of characteristic yellow deposits, called drusen (buildup of extracellular proteins and lipids), in the macula (a part of the retina), between the retinal pigment epithelium and the underlying choroid. This accumulation is believed to damage the retina over time. Amyloid beta, which builds up in Alzheimers disease brains, is one of the proteins that accumulate in AMD, which is a reason why AMD is sometimes called "Alzheimers of the eye" or "Alzheimers of the retina".
Cerebro-costo-mandibular syndrome is a very rare genetic disorder which is characterized by jaw/chin, palate and rib abnormalities. Signs and symptoms
The following list comprises the most common symptoms people with this disorder exhibit:
Severe micrognathia
Thorax in the shape of a bell
Cleft palate
Neonatal respiratory difficulties
Rib gapsCommon (but not the most) symptoms include:

External auditory canal atresia
Hearing loss
Failure to thrive
Glossoptosis
Intellectual disabilities
Fetal growth delays
Kyphosis
Short height
TracheomalaciaNot common but also not rare symptoms include:

Fifth finger clinodactyly
Cerebral calcification
Hydranencephaly
Meningocele
Microcephaly
Polycystic kidney dysplasia
Myelomeningocele
Porencephalic cyst
Short, hard palate
Spina bifida
Ventricular septal defect
Webbed neck

Causes
This disorder is caused by autosomal dominant mutations in the SNRPB gene, in chromosome 20. Epidemiology
Only 110 cases have been described in medical literature. == References ==