remim: Random-effect multiple interval mapping (REMIM)

Description Usage Arguments Value Author(s) References See Also Examples

View source: R/remim.R

Description

Automatic function that performs REMIM algorithm using score statistics.

Usage

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remim(
  data,
  pheno.col = NULL,
  w.size = 15,
  sig.fwd = 0.01,
  sig.bwd = 1e-04,
  score.null = NULL,
  d.sint = 1.5,
  polygenes = FALSE,
  n.clusters = NULL,
  n.rounds = Inf,
  plot = "remim",
  verbose = TRUE
)

## S3 method for class 'qtlpoly.remim'
print(x, pheno.col = NULL, sint = NULL)

Arguments

data

an object of class qtlpoly.data.

pheno.col

a numeric vector with the phenotype columns to be analyzed or printed; if NULL (default), all phenotypes from 'data' will be included.

w.size

the window size (in centiMorgans) to avoid on either side of QTL already in the model when looking for a new QTL, e.g. 15 (default).

sig.fwd

the desired score-based significance level for forward search, e.g. 0.01 (default).

sig.bwd

the desired score-based significance level for backward elimination, e.g. 0.001 (default).

score.null

an object of class qtlpoly.null with results of score statistics from resampling.

d.sint

a d value to subtract from logarithm of p-value (LOP-d) for support interval calculation, e.g. d=1.5 (default) represents approximate 95% support interval.

polygenes

if TRUE all QTL already in the model are treated as a single polygenic effect; if FALSE (default) all QTL effect variances have to estimated.

n.clusters

number of parallel processes to spawn.

n.rounds

number of search rounds; if Inf (default) forward search will stop when no more significant positions can be found.

plot

a suffix for the file's name containing plots of every algorithm step, e.g. "remim" (default); if NULL, no file is produced.

verbose

if TRUE (default), current progress is shown; if FALSE, no output is produced.

x

an object of class qtlpoly.remim to be printed.

sint

whether "upper" or "lower" support intervals should be printed; if NULL (default), only QTL peak information will be printed.

Value

An object of class qtlpoly.remim which contains a list of results for each trait with the following components:

pheno.col

a phenotype column number.

stat

a vector containing values from score statistics.

pval

a vector containing p-values from score statistics.

qtls

a data frame with information from the mapped QTL.

lower

a data frame with information from the lower support interval of mapped QTL.

upper

a data frame with information from the upper support interval of mapped QTL.

Author(s)

Guilherme da Silva Pereira, gdasilv@ncsu.edu

References

Kao CH, Zeng ZB, Teasdale RD (1999) Multiple interval mapping for quantitative trait loci. Genetics 152 (3): 1203–16. www.genetics.org/content/152/3/1203.

Pereira GS, Gemenet DC, Mollinari M, Olukolu BA, Wood JC, Mosquera V, Gruneberg WJ, Khan A, Buell CR, Yencho GC, Zeng ZB (2020) Multiple QTL mapping in autopolyploids: a random-effect model approach with application in a hexaploid sweetpotato full-sib population, Genetics 215 (3): 579-595. http://doi.org/10.1534/genetics.120.303080.

Qu L, Guennel T, Marshall SL (2013) Linear score tests for variance components in linear mixed models and applications to genetic association studies. Biometrics 69 (4): 883–92. doi.org/10.1111/biom.12095.

Zou F, Fine JP, Hu J, Lin DY (2004) An efficient resampling method for assessing genome-wide statistical significance in mapping quantitative trait loci. Genetics 168 (4): 2307-16. doi.org/10.1534/genetics.104.031427

See Also

read_data

Examples

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  ## Not run: 
  # load raw data
  data(maps)
  data(pheno)

  # estimate conditional probabilities using mappoly package
  library(mappoly)
  genoprob <- lapply(maps, calc_genoprob)

  # prepare data
  data <- read_data(ploidy = 6, geno.prob = genoprob, pheno = pheno, step = 1)

  # perform remim
  remim.mod <- remim(data = data, w.size = 15, sig.fwd = 0.01, sig.bwd = 0.0001,
    d.sint = 1.5, n.clusters = 4, plot = "remim")
  
## End(Not run)

guilherme-pereira/QTLpoly documentation built on Oct. 10, 2021, 10:22 p.m.