Human Genetics

, Volume 110, Issue 1, pp 95–97

The USH1C 216G→A mutation and the 9-repeat VNTR(t,t) allele are in complete linkage disequilibrium in the Acadian population

  • Sevtap Savas
  • Ben Frischhertz
  • Mary Z. Pelias
  • Mark A. Batzer
  • Prescott L. Deininger
  • Bronya J. Keats
Short Report

DOI: 10.1007/s00439-001-0653-7

Cite this article as:
Savas, S., Frischhertz, B., Pelias, M.Z. et al. Hum Genet (2002) 110: 95. doi:10.1007/s00439-001-0653-7

Abstract.

Recently, mutations in USH1C were shown to be associated with Usher syndrome type IC, and a mutation (216G→A) in exon 3 was identified in an Acadian family. In addition, a 45-bp variable number of tandem repeat (VNTR) polymorphism was found in intron 5 of USH1C. Polymerase chain reaction amplification of the VNTR region and restriction enzyme analysis of exon 3 of USH1C showed that, of 44 Acadian patients, 43 were homozygous for both the 216G→A mutation and nine repeats of the VNTR, with a "t" nucleotide replacing a "g" nucleotide at the 8th position of both the eighth and ninth copies of the repeat, viz., 9VNTR(t,t). The remaining Acadian patient was reported to be a compound heterozygote for 216G→A/9VNTR(t,t) and 238–239insC, a USH1C mutation that has been found in other populations. These data demonstrate that the 9VNTR(t,t) allele is in complete linkage disequilibrium with the 216G→A mutation in the Acadian population. Among 82 Acadian controls, one was heterozygous for 216G→A/9VNTR(t,t). The 238–239insC mutation was not found in Acadian controls. Analysis of 340 non-Acadian normal samples showed the presence of a 9-repeat VNTR allele in one Hispanic sample. This individual had neither the 216G→A mutation nor the Acadian VNTR(t,t) structure. These results suggest that the 216G→A mutation and the 9VNTR(t,t) allele are restricted to the Acadians and are in complete linkage disequilibrium.

Copyright information

© Springer-Verlag 2001

Authors and Affiliations

  • Sevtap Savas
    • 1
  • Ben Frischhertz
    • 2
  • Mary Z. Pelias
    • 1
  • Mark A. Batzer
    • 3
  • Prescott L. Deininger
    • 2
  • Bronya J. Keats
    • 1
  1. 1.Department of Genetics, Louisiana State University Health Sciences Center, 533 Bolivar Street, New Orleans, LA 70112, USAUSA
  2. 2.Tulane Cancer Center, Department of Environmental Health Sciences, New Orleans, LA, USAUSA
  3. 3.Department of Biological Sciences, Biological Computation and Visualization Center, Louisiana State University, Baton Rouge, LA, USAUSA