R help - Dec 2005 - Accounting for within family correlation in genetic analysis

I am hoping for help with a genetic analysis.

I am trying to perform an analysis of the relation between genes at a given
locus (rs2304795) and a phenotypic trait (zerotg). Multiple subjects are
recruited from each family (and so share a part of their genome and are
correlated). Family groups are identified by the variable FAMILY. For each
subject multiple measurements are made of the trait of interest (zerotg) over
the course of several hours (time). The data within each subject are of course
correlated and over time each subject's response is curvilinear. I know how
to deal with the within subject correlation using a growth-curve analysis:

	zerotgQuad0ML.lme <- 
		lme (zerotg ~ time + time^2 + rs2304795 + rs2304795 * time +   rs2304795 *
time^2,
			data = GC, random =  ~ 1 + time + time^2 | HAPI, 
                      		na.action = na.omit, method = "REML") 

but I don't know how I can modify the model to account for the within-family
correlation.

I would appreciate any suggestions for modifications to the code above that
would allow me to account for the within-family correlation of observations.

Thanks,
John

John Sorkin M.D., Ph.D.
Chief, Biostatistics and Informatics
Baltimore VA Medical Center GRECC and
University of Maryland School of Medicine Claude Pepper OAIC

University of Maryland School of Medicine
Division of Gerontology
Baltimore VA Medical Center
10 North Greene Street
GRECC (BT/18/GR)
Baltimore, MD 21201-1524

410-605-7119 
- NOTE NEW EMAIL ADDRESS:
jsorkin at grecc.umaryland.edu