University of Michigan Center for Statistical 




Linkage Disequilibrium Analyses for Quantitative and Discrete Traits

QTDT provides a convenient one-stop interface for family based tests of linkage disequilibrium. The general models described by Abecasis et al. (2000a, b) are supported, and can be used to analyse quantitative or discrete traits in nuclear families, with or without parental genotypes, or extended pedigrees. In addition, QTDT can calculate exact p-values by permutation even when multiple linked polymorphisms are tested. The tests described by Allison (TDTQ5, 1997), Rabinowitz (1997), Monks et al. (1998) and Fulker et al. (1999) are also supported.

Background Information

Read about family based disequilibrium analysis and QTDT.

 Quick-Start Tutorial

Take a tour of the QTDT package. Recommended.

Browse documentation

The online documentation includes information on file formats and known bugs.

Download programs

Download the latest version of the programs. [Updated August 2008]

Registration form

If you decide to use QTDT, please take a minute to let us know.


University of Michigan | School of Public Health | Abecasis Lab