A Trisomic Transmission Disequilibrium Test

Zhiying Xu, Kimberly F. Kerstann, Stephanie L. Sherman, Aravinda Chakravarti, Eleanor Feingold

Research output: Contribution to journalArticlepeer-review


Certain congenital disorders that are rare in the general population are quite common in individuals with trisomic conditions. For example, complete atrioventricular septal defect occurs in about 20% of individuals with Down syndrome, an approximately 500-fold increase in risk as compared to individuals without Down syndrome. Genetic variation on the chromosome involved in the trisomy may affect susceptibility to these trisomy-specific disorders. That is, increased dosage of a variant may be directly involved in increasing the risk of a disorder, or it may be indirectly involved by causing up- or downregulation of other genes. As in standard disomic gene-mapping, one can search for genes using linkage or association methods. Within association methods, one can consider case-control methods or family-based control methods such as the transmission disequilibrium test (TDT). Most gene-mapping methods need to be substantially redesigned for use with trisomic data. In this paper, we present a "trisomic TDT", a statistical method of testing for nonrandom transmission of alleles from parents to trisomic children. We demonstrate the method on a dataset of parent-child trios in which the child has Down syndrome.

Original languageEnglish (US)
Pages (from-to)125-131
Number of pages7
JournalGenetic epidemiology
Issue number2
StatePublished - Feb 2004


  • Association testing
  • Down syndrome
  • TDT
  • Trisomy

ASJC Scopus subject areas

  • Epidemiology
  • Genetics(clinical)


Dive into the research topics of 'A Trisomic Transmission Disequilibrium Test'. Together they form a unique fingerprint.

Cite this