Analysis of discrete phenotypes using a multipoint
identity-by-descent method: application to Alzheimer's disease
D.E. Goldgar, C.M. Lewis, K. Gholami
Genetic Epidemiology, 10(6),383-388
(1993)
Abstract
The multipoint identity-by-descent method was developed to detect
linkage to a specific chromosomal region through partitioning the
genetic variance. This method has previously been applied to
quantitative traits, and here is extended to a qualitative trait,
where a dichotomous affected/unaffected status variable is
transformed to a quantitative variable by incorporating covariates.
This method is applied to the Alzheimer's disease data sets from
Genetic Analysis Workshop 8, to investigate putative linkage to
chromosomes 19 and 21. The multipoint identity-by-descent method is
used to test for linkage through the qualitative trait, and for
excess sharing of the chromosomal region among affected sibs.
Results are compared to those of the affected-pedigree-member method
and classical linkage analysis. None of these methods gave results
showing clear linkage, with the only marginally significant results
occurring for the Boston data set on chromosome 19 and the Duke data
set for chromosome 21 using the multipoint identity-by-descent
method.
Allele-sharing linkage analysis