makeqtl {qtl} | R Documentation |
This function takes a cross object and specified chromosome numbers
and positions and pulls out the genotype probabilities and/or imputed
genotypes at the nearest pseudomarkers, for later use by the function
fitqtl
.
makeqtl(cross, chr, pos, qtl.name)
cross |
An object of class cross . See
read.cross for details. |
chr |
Vector indicating the chromosome for each QTL. |
pos |
Vector (of same length as chr ) indicating the
positions on the chromosome to be taken. If there's no marker or
pseudomarker at a position, genotypes for the nearest positions are
taken. |
qtl.name |
The user-specified name for each QTL, used in the
drop-one-term ANOVA table in fitqtl .
If unspecified, the names will be of the form "Chr1@10" for a
QTL on Chromsome 1 at 10 cM. |
This function will take out the genotype probabilities and imputed
genotypes if they are present in the input cross
object. If both
fields are missing in the input object, the function will report an
error. Before running this function, the user must have first run either
calc.geno
or sim.geno
.
An object of class qtl
with the following elements:
geno |
Imputed genotypes. |
prob |
Genotype probabilities. |
chr |
Input vector of chromosome numbers. |
pos |
Input vector of chromosome positions. |
n.qtl |
Number of QTLs. |
n.ind |
Number of individuals. |
n.gen |
A vector indicating the number of genotypes for each QTL. |
Hao Wu, hao@jax.org
Sen, S. and Churchill, G. A. (2001) A statistical framework for quantitative trait mapping. Genetics 159, 371–387.
fitqtl
, calc.genoprob
,
sim.geno
data(fake.f2) # take out several QTLs and make QTL object qc <- c(1, 6, 13) qp <- c(25.8, 33.6, 18.63) fake.f2 <- subset(fake.f2, chr=qc) fake.f2 <- sim.geno(fake.f2, n.draws=8, step=2, err=0.001) qtl <- makeqtl(fake.f2, qc, qp)