Furthermore, recent studies have also implied the proteins role in cathepsin D deficiency; the overexpression of the defective protein appears to have significant effects on cathepsin D processing, with implications suggesting that accumulation of ATP synthase subunit C would result. Only recently have studies of human patients shown deficiency of lysosomal aspartyl proteinase cathepsin D.

Adult dominant form
Between 1.3 and 10% of cases are of the adult form. The age at onset is variable (6–62 yr). Two main clinical subtypes have been described: progressive myoclonus epilepsy (type A) and dementia with motor disturbances, such as cerebellar, extrapyramidal signs and dyskinesia (type B). Unlike the other NCLs, retinal degeneration is absent. Pathologically, the ceroid-lipofuscin accumulates mainly in neurons and contains subunit C of the mitochondrial ATP synthase.Two independent families have been shown to have mutations in the DNAJC5 gene – one with a transversion and the other with a deletion mutation. The mutations occur in a cysteine-string domain, which is required for membrane targeting/binding, palmitoylation, and oligomerization of the encoded protein cysteine-string protein alpha (CSPα). The mutations dramatically decrease the affinity of CSPα for the membrane. A second report has also located this disease to this gene. Treatment
Currently, no widely accepted treatment can cure, slow down, or halt the symptoms in the great majority of patients with NCL, but seizures may be controlled or reduced with use of antiepileptic drugs. Additionally, physical, speech, and occupational therapies may help affected patients retain functioning for as long as possible. Several experimental treatments are under investigation.
The facial skin may be dry, exfoliative (flaking) or erythematous. Cervical lymphadenopathy (enlarged lymph nodes in the neck). Facial palsy (weakness and altered sensation of the face).The enlargement of the tissues of the mouth, lips and face seen in OFG is painless. Melkersson–Rosenthal syndrome is where OFG occurs with fissured tongue and paralysis of the facial nerve. The cause of the facial paralysis is thought to be caused by the formation of granulomas in the facial nerve, which supplies the muscles of facial expression. Causes
The cause of the condition is unknown. The disease is characterized by non-caseating granulomatous inflammation. That is, the granulomas do not undergo the caseating ("cheese-like") necrosis typical of the granulomas of tuberculosis. There is disagreement as to whether OFG represents an early form of Crohn disease or sarcoidosis, or whether it is a distinct, but similar clinical entity. Crohn disease can affect any part of gastrointestinal tract, from mouth to anus. When it involves the mouth alone, some authors refer to this as "oral Crohn disease", distinguishing it from OFG, and others suggest that OFG is the same condition as Crohn disease when it presents in the oral cavity. OFG may represent a delayed hypersensitivity reaction, but the causative antigen(s) is not identified or varies form one individual to the next. Suspected sources of antigens include metals, e.g.