Improved conditions for the analysis of large variable number of tandemly repeated (VNTR) unit polymorphisms

Koen Vandenbroeck, Antonella Consiglio, Gianvito Martino, Luigi M E Grimaldi

Research output: Contribution to journalArticle


Large variable number of tandemly repeated (VNTR) unit polymorphisms were identified by amplification of genomic DNA with appropriate primers, followed by agarose gel electrophoresis and ethidium bromide staining. However, when genomic DNA was extracted using paramagnetic beads, we found that the efficiency of polymerase chain reaction amplification of VNTR's was affected by the purity of the solid phase-eluted DNA. Here we report that VNTR's located in the human interleukin-l receptor antagonist and interleukin-4 genes are clearly and reliably amplified only when more stringent conditions are used in order to obtain purer DNA eluates from DNA-bead complexes. In addition, polyacrylamide gel electrophoresis followed by silver staining is superior to ethidium bromide staining of agarose gels in visualizing the different allelic bands of heterozygous carriers.

Original languageEnglish
Pages (from-to)678-680
Number of pages3
Issue number4
Publication statusPublished - Apr 1996



  • Paramagnetic beads
  • Polyacrylamide gel electrophoresis
  • Polymerase chain reaction
  • Polymorphism
  • Variable number of tandem repeats

ASJC Scopus subject areas

  • Clinical Biochemistry

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