Skip to Content

As a result of the current Federal government funding situation, the information on this website may not be up to date or acted upon.

The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit https://cc.nih.gov.

Updates regarding government operating status and resumption of normal operations can be found at https://www.opm.gov.

Discovering the causes of cancer and the means of prevention

Publications Search - Abstract View

Title: The equivalence of two tests and models for HLA data with no observed double blanks.
Authors: Gart JJ,  Nam JM
Journal: Biometrics
Date: 1988 Sep
Branches: BB
PubMed ID: 3203134
PMC ID: not available
Abstract: Gart and Nam (1984, Biometrics 40, 887-894) consider the analysis of an ABO-like model based on the Hardy-Weinberg law in the commonly occurring case of human leukocyte antigen (HLA) data where there are no double blanks, that is, no recessive homozygotes. They derive a score test, based on the truncated likelihood, of the hypothesis that the true recessive gene (or allele) frequency is zero. Yasuda (1968, Biometrics 24, 915-935) considers a similar codominant system wherein the true recessive gene frequency is assumed zero, but the Hardy-Weinberg law does not hold. In particular, he considers the possibility of a nonzero inbreeding coefficient. We show that the two models are equivalent; each likelihood can be shown to be a reparameterization of the other. Furthermore, the score test of the zero gene frequency in Gart and Nam is identical to the score test for a zero inbreeding coefficient given by Yasuda. The results are applied to an example wherein it appears that the Hardy-Weinberg model is appropriate. Thus, it is not possible in this population to identify homozygous individuals without error from phenotypic data alone.