[R] how to do association study based on mixed linear model

[Yao He]

Dear All:

I want to do association study based on mixed linear model,

My model not only includes serval fixed effects and random effects but
also incorporates some covariates such as "birth weight".
Otherwise, the size of the data are about 180 individuals and 12
variables and 60000 Fixed effect estimates

As asreml-R is not free ,is there any packages for my study?
I heard  nlme or lme4 but I'm not sure whether they could incorporate
covariates and what about their computational efficiency?

Thanks for you recommendation

Yao He
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Master candidate in 2rd year
Department of Animal genetics & breeding
Room 436,College of Animial Science&Technology,
China Agriculture University,Beijing,100193
E-mail: yao.h.1988 at gmail.com
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