The transmission/disequilibrium test for linkage on the X chromosome

Gloria Y.F. Ho, Joan E. Bailey-Wilson

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


The transmission/disequilibrium test (TDT), which detects linkage between a marker and disease loci in the presence of linkage disequilibrium, was introduced by Spielman et al. The original TDT requires families in which the genotypes are known for both parents and for at least one affected offspring, and this limits its applicability to diseases with late onset. The sib-TDT, or S-TDT, which utilizes families with affected and unaffected siblings, was introduced as an alternative method, by Spielman and Ewens, and the TDT and S-TDT can be combined in an overall test (i.e., a combined-TDT, or C-TDT). The TDT statistics described so far are for autosomal chromosomes. We have extended these TDT methods to test for linkage between X-linked markers and diseases that affect either males only or both sexes. For diseases of late onset, when parental genotypes are often unavailable, the X- linkage C-TDT may allow for more power than is provided by the X-linkage TDT alone.

Original languageEnglish (US)
Pages (from-to)1158-1160
Number of pages3
JournalAmerican Journal of Human Genetics
Issue number3
StatePublished - 2000
Externally publishedYes

ASJC Scopus subject areas

  • Genetics
  • Genetics(clinical)


Dive into the research topics of 'The transmission/disequilibrium test for linkage on the X chromosome'. Together they form a unique fingerprint.

Cite this