Document Detail

Origin and instability of GAA repeats: insights from Alu elements.
MedLine Citation:
PMID:  12354077     Owner:  NLM     Status:  MEDLINE    
Expansion of GAA repeats in the intron of the frataxin gene is involved in the autosomal recessive Friedreich's ataxia (FRDA). The GAA repeats arise from a stretch of adenine residues of an Alu element. These repeats have a size ranging from 7- 38 in the normal population, and expand to thousands in the affected individuals. The mechanism of origin of GAA repeats, their polymorphism and stability are not well understood. In this study, we have carried out an extensive analysis of GAA repeats at several loci in the humans. This analysis indicates the association of a majority of GAA repeats with the 3' end of an "A" stretch present in the Alu repeats. Further, the prevalence of GAA repeats correlates with the evolutionary age of Alu subfamilies as well as with their relative frequency in the genome. Our study on GAA repeat polymorphism at some loci in the normal population reveals that the length of the GAA repeats is determined by the relative length of the flanking A stretch. Based on these observations, a possible mechanism for origin of GAA repeats and modulatory effects of flanking sequences on repeat instability mediated by DNA triplex is proposed.
Chitra Chauhan; Debasis Dash; Deepak Grover; Jaya Rajamani; Mitali Mukerji
Related Documents :
2575587 - Isolation of a novel mildly repetitive dna sequence that is predominantly located at th...
16358217 - A y-chromosome signature of hegemony in gaelic ireland.
10434307 - Molecular pathology of dentatorubral-pallidoluysian atrophy.
18160787 - Similarities in the chromosomal distribution of ag and ac repeats within and between dr...
12366717 - Myelodysplastic syndrome in transformation to acute myeloid leukemia presenting with di...
2893547 - Chromosomal localization of the human proenkephalin and prodynorphin genes.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of biomolecular structure & dynamics     Volume:  20     ISSN:  0739-1102     ISO Abbreviation:  J. Biomol. Struct. Dyn.     Publication Date:  2002 Oct 
Date Detail:
Created Date:  2002-09-30     Completed Date:  2003-05-02     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  8404176     Medline TA:  J Biomol Struct Dyn     Country:  United States    
Other Details:
Languages:  eng     Pagination:  253-63     Citation Subset:  IM    
Functional Genomics Unit, Centre for Biochemical Technology (CSIR), Delhi University Campus, Mall Road, Delhi-110007, India.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
3' Flanking Region
Adenine / chemistry
Alu Elements / genetics*
Chromosomes, Human, Pair 22
Databases, Genetic
Evolution, Molecular
Friedreich Ataxia / epidemiology,  genetics
Gene Frequency
Genes, Recessive
Genome, Human
Iron-Binding Proteins / genetics
Models, Genetic
Polymorphism, Genetic
Trinucleotide Repeat Expansion / genetics
Trinucleotide Repeats / genetics*
Reg. No./Substance:
0/Iron-Binding Proteins; 0/frataxin; 73-24-5/Adenine

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Flexibility of BIV TAR-Tat: models of peptide binding.
Next Document:  Design and structural analysis of hairpin-TFO for transcriptional activation of genes in S. cerevisi...