A ribbon diagram of apolipoprotein E. Variants of this protein influence the risk of developing DLB. Like other synucleinopathies, the exact cause of DLB is unknown. No trigger for the build-up of alpha-synuclein deposits in the central nervous system has been conclusively identified. Synucleinopathies are typically caused by interactions of genetic and environmental influences; infectious causes have also been considered, but arguments in their favor are controversial and lacking in support. Most people with DLB do not have affected family members, although occasionally DLB runs in a family. The heritability of DLB is thought to be around 30% (that is, about 70% of traits associated with DLB are not inherited). There is overlap in the genetic risk factors for DLB, Alzheimer's disease (AD), Parkinson's disease, and Parkinson's disease dementia. The APOE gene has three common variants. One, APOE ε4, is a risk factor for DLB and Alzheimer's disease, whereas APOE ε2 may be protective against both. Mutations in GBA, a gene for a lysosomal enzyme, are associated with both DLB and Parkinson's disease. Rarely, mutations in SNCA, the gene for alpha-synuclein, or LRRK2, a gene for a kinase enzyme, can cause any of DLB, Alzheimer's disease, Parkinson's disease or Parkinson's disease dementia. This suggests some shared genetic pathology may underlie all four diseases. The greatest risk of developing DLB is being over the age of 50. Having REM sleep behavior disorder or Parkinson's disease confers a higher risk for developing DLB. The risk of developing DLB has not been linked to any specific lifestyle factors. Risk factors for rapid conversion of RBD to a synucleinopathy include impairments in color vision or the ability to smell, mild cognitive impairment, and abnormal dopaminergic imaging.
medical cause of Parkinsonism
medical cause of Dementia
symptom of Pantothenate kinase-associated neurodegeneration
complications of Myotonic dystrophy
symptom of Amyotrophic lateral sclerosis
symptom of Spinocerebellar ataxia type 1
medical cause of Polyneuropathy
medical cause of Dystonia