Copyright © 1999 The American Society of Human Genetics. All rights reserved.
The American Journal of Human Genetics, Volume 65, Issue 4, 1170-1177, 1 October 1999
doi:10.1086/302577
A Generalization of the Transmission/Disequilibrium Test for Uncertain-Haplotype Transmission
David Clayton
, 
MRC Biostatistics Unit, Institute of Public Health, Cambridge
Address for correspondence and reprints: Dr. David Clayton, MRC Biostatistics Unit, Institute of Public Health, University Forvie Site, Robinson Way, Cambridge CB2 2SR, United KingdomAbstract
A new transmission/disequilibrium-test statistic is proposed for situations in which transmission is uncertain. Such situations arise when transmission of a multilocus marker haplotype is considered, since haplotype phase is often unknown in a substantial number of instances. Even for single-locus markers, transmission is uncertain if one or both parents are missing. In both these situations, uncertainty may be reduced by the typing of further siblings, whose disease status may be unaffected or unknown. The proposed test is a score test based on a partial score function that omits the terms most influenced by hidden population stratification.
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