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QTDT is a tool for the analysis of linkage disequilibrium (LD) of Quantitative and Discrete Traits. The QTDT has algorithms for exact p-values by permutation although when testing multiple linked polymorphisms, tests described by Allison (TDTQ5, 1997), Rabinowitz (1997), Monks et al. (1998), Fulker et al. (1999), and association models: Abecasis (2000), the models of Allison (1997, TDTQ5), Rabinowitz (1997), Monks (1998) and Fulker (2000).


GWAS study


  • Operation: Linkage disequilibrium calculation
  • Input: QTDT requires matched data and pedigree files as input. An optional IBD information file is recommended for variance component analyses.
  • Output: -
  • Software interface: Command-line user interface
  • Language: C++
  • Operating system: Linux; Mac OS X; Microsoft Windows
  • License: BSD-3-Clause
  • Cost: Free
  • Version name: 2.6.1
  • Maturity: Mature
  • Credit: -
  • Contact: gonzalo _at_
  • Collection: -


Abecasis GR, Cardon LR, Cookson WO "A general test of association for quantitative traits in nuclear families." Am J Hum Genet. 2000 Jan;66(1):279-92.
PMID: 10631157
PMCID: PMC1288332

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