[R-sig-ME] User defined variance-covariance matrix of random effects

[David Duffy]

On Tue, 11 Nov 2008, Marc Moragues Canela wrote:

> Dear all,
>
> I am trying to build a mixed model to do association mapping of QTL.
> Basically I want to know if a marker is correlated with a trait. I know
> there are some packages that do this type of analysis like GenABEL, but I
> need more flexibility to modify the model to include, for example, the
> genotype by environment interaction.
>

You will have to use the kinship package, which uses lme.  It is 
pretty fast, unless you have very large pedigrees.  Doug Bates and 
others are still working on a lmer based equivalent.

David Duffy.
-- 
| David Duffy (MBBS PhD)                                         ,-_|\
| email: davidD at qimr.edu.au  ph: INT+61+7+3362-0217 fax: -0101  /     *
| Epidemiology Unit, Queensland Institute of Medical Research   \_,-._/
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