This raises the possibility of other undiagnosed mildly involved patients. The diagnosis should be considered in retarded Jewish children who have corneal clouding. The electron microscopic demostration of characteristic storage bodies in a conjunctival biopsy supports the clinical diagnosis. The specific biochemical and genetic defects which cause ML4 are not known. Current research has focused on a possible defect in the metabolism of phospholipids and gangliosides.
Further research is required to identify the specific enzyme abnormality.
This will permit the development of precise methods for diagnosis including identification of carriers of the gene which causes ML4. The disease is inherited as an autosomal recessive trait. Although both parents are normal, they carry the disease-causing gene. The prenatal diagnosis of this disease has been successfully accomplished by electron microscopic demonstration of characterisic storage bodies in cultured amniotic cells obtained by amniocentesis. The prenatal diagnosis is difficult and must be performed in centers with expertise in the specialized techniques required for this diagnosis.