A high frequency of length polymorphisms in repeated sequences adjacent to Alu sequences

Giovanni Zuliani, Helen H. Hobbs

Research output: Contribution to journalArticle

100 Scopus citations

Abstract

We describe a new class of DNA length polymorphism that is due to a variation in the number of tandem repeats associated with Alu sequences (Alu sequence-related polymorphisms). The polymerase chain reaction was used to selectively amplify a (TTA)(n) repeat identified in the 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase gene from genomic DNA of 41 human subjects, and the size of the amplified products was determined by gel electrophoresis. Seven alleles were found that differed in size by integrals of three nucleotides. The allele frequencies ranged from 1.5% to 52%, and the overall heterozygosity index was 62%. The polymorphic TTA repeat was located adjacent to a repetitive sequence of the Alu family. A homology search of human genomic DNA sequences for the trinucleotide TTA (at least five members in length) revealed tandem repeats in six other genes. Three of the six (TTA)(n) repeats were located adjacent to Alu sequences, and two of the three (in the genes for β-tubulin and interleukin-1α) were found to be polymorphic in length. Tandemly repetitive sequences found in association with Alu sequence may be frequent sites of length polymorphism that can be used as genetic markers for gene mapping or linkage analysis.

Original languageEnglish (US)
Pages (from-to)963-969
Number of pages7
JournalAmerican Journal of Human Genetics
Volume46
Issue number5
StatePublished - May 23 1990

ASJC Scopus subject areas

  • Genetics
  • Genetics(clinical)

Fingerprint Dive into the research topics of 'A high frequency of length polymorphisms in repeated sequences adjacent to Alu sequences'. Together they form a unique fingerprint.

  • Cite this