(This article was first published on Getting Genetics Done, and kindly contributed to R-bloggers)
I recently did an analysis for the eMERGE network where I had lots of individuals from a small town in central Wisconsin where many of the subjects were related to one another. The subjects could not be treated as independent, but I could not use a family-based design either. I ended up using a mixed model approach using previously mentioned GenABEL. You can read about the method here (PubMed).
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