Gene counting for haplotype analysis
Arguments
- data
genotype table.
- weight
a column of frequency weights.
- loci
an array containing number of alleles at each locus.
- control
is a function with the following arguments:
xdata. a flag indicating if the data involves X chromosome, if so, the first column of data indicates sex of each subject: 1=male, 2=female. The marker data are no different from the autosomal version for females, but for males, two copies of the single allele present at a given locus.
convll. set convergence criteria according to log-likelihood, if its value set to 1
handle.miss. to handle missing data, if its value set to 1
eps. the actual convergence criteria, with default value 1e-5
tol. tolerance for genotype probabilities with default value 1e-8
maxit. maximum number of iterations, with default value 50
pl. criteria for trimming haplotypes according to posterior probabilities
assignment. filename containing haplotype assignment
verbose. If TRUE, yields print out from the C routine
Value
The returned value is a list containing:
h haplotype frequency estimates under linkage disequilibrium (LD).
h0 haplotype frequency estimates under linkage equilibrium (no LD).
prob genotype probability estimates.
l0 log-likelihood under linkage equilibrium.
l1 log-likelihood under linkage disequilibrium.
hapid unique haplotype identifier (defunct, see
gc.em).npusr number of parameters according user-given alleles.
npdat number of parameters according to observed.
htrtable design matrix for haplotype trend regression (defunct, see
gc.em).iter number of iterations used in gene counting.
converge a flag indicating convergence status of gene counting.
di0 haplotype diversity under no LD, defined as \(1-\sum (h_0^2)\).
di1 haplotype diversity under LD, defined as \(1-\sum (h^2))\).
resid residuals in terms of frequency weights = o - e.
References
Zhao JH, Lissarrague S, Essioux L, Sham PC (2002). “GENECOUNTING: haplotype analysis with missing genotypes.” Bioinformatics, 18(12), 1694-5. doi:10.1093/bioinformatics/18.12.1694 .
Zhao JH, Sham PC (2003). “Generic number systems and haplotype analysis.” Comput Methods Programs Biomed, 70(1), 1-9. doi:10.1016/s0169-2607(01)00193-6 .
Zhao JH (2004). “2LD. GENECOUNTING and HAP: computer programs for linkage disequilibrium analysis.” Bioinformatics, 20(8), 1325-6. doi:10.1093/bioinformatics/bth071 .
Examples
if (FALSE) { # \dontrun{
require(gap.datasets)
# HLA data
data(hla)
hla.gc <- genecounting(hla[,3:8])
summary(hla.gc)
hla.gc$l0
hla.gc$l1
# ALDH2 data
data(aldh2)
control <- gc.control(handle.miss=1,assignment="ALDH2.out")
aldh2.gc <- genecounting(aldh2[,3:6],control=control)
summary(aldh2.gc)
aldh2.gc$l0
aldh2.gc$l1
# Chromosome X data
# assuming allelic data have been extracted in columns 3-13
# and column 3 is sex
filespec <- system.file("tests/genecounting/mao.dat")
mao2 <- read.table(filespec)
dat <- mao2[,3:13]
loci <- c(12,9,6,5,3)
contr <- gc.control(xdata=TRUE,handle.miss=1)
mao.gc <- genecounting(dat,loci=loci,control=contr)
mao.gc$npusr
mao.gc$npdat
} # }