Advances in molecular genetics marked the major advances last year in neurology; however, major developments also occurred in other areas, particularly in new types of therapy. Late last year, two excellent reviews summarizing advances in the genetics of neurologic diseases were published.1,2 The unstable trinucleotide repeat continues to turn up as the genetic defect in several inherited neurologic disorders, including Huntington's disease, spinobulbar muscular atrophy, myotonic dystrophy, and spinocerebellar ataxia type 1.1,2 The number of repeats is related to severity or latency in the different disorders.
Late-onset familial Alzheimer's disease (FAD) has been associated with a defect on chromosome 19.3 The defect is linked with apolipoprotein E, which transports cholesterol into the brain. Apolipoprotein E binds with amyloid and is found with amyloid and with the neurofibrillary tangles in the brain of those with Alzheimer's disease. The E4 allele of apolipoprotein E is found in 45% of
Joynt RJ. Neurology. JAMA. 1994;271(21):1686-1687. doi:10.1001/jama.1994.03510450058032