Trinucleotide repeat disorders

Trinucleotide repeat disorders. Annual Revieiv of Neuroscience, 30, 575-621. 

Cummings Cl, Zoghbi HY (2000) Eourteen and counting unravehng trinucleotide repeat disorders. Human Mol Genet 9 909-916... 

Thi autosomal dominant disorder, which affects approximately 1 in 8,000 individuals, is characterized by progressive muscle deterioration, cardiac arrhythmia, testicular atrophy, frontal baldness, and cataraas. As noted above, most cases are caused by a trinucleotide repeat expansion in the 3 UTR of a gene that encodes a protein kinase. Larger repeat numbers lead to earlier and more severe expression of the disease (anticipation). Especially large expansions sometimes occur in maternal transmission of the trinucleotide repeat, resulting in a severe neonatal form of the disorder. 

Examp 1 es of genetic diseases that show anticipation are Huntington disease, Fragile X syndrome, and other disorders that arise from trinucleotide repeat... 

Huntington s disease is an autosomal dominant inherited disorder caused by an abnormality (expansion of a CAG trinucleotide repeat that codes for a polyglutamine tract) of the huntingtin gene on chromosome 4. An autosomal... 

Huntington disease A progressive and fatal disorder of the nervous system that develops between the ages of 30 and 50 years caused by an expansion of a trinucleotide repeat and inherited as a dominant trait. 

Expansion of trinucleotide repeat sequences is the mutational mechanism in at least 16 neurological disorders,... 

HD is an autosomal dominant disorder with nearly complete penetrance. In affected individuals, the short arm of chromosome 4 contains a polymorphic (CAG) trinucleotide repeat that is significantly expanded in all individuals with HD this trinucleotide repeat is the genetic alteration... 

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