Before the gwaspr package can be used, we first need to
run GWAS with GAPIT.
Genotype data (myG)
Our population, the LDP, was genotyped using an exome caputure
array and filtered with the following criteria to yield a data set
of 336,367 SNPs, stored in our object myG.
- Only Bi-allelic = TRUE
- Minimum Read Depth = 3
- Minor Allele Frequency = >5%
- Maximum Missing Frequency = 25%
- Heterozygous = <25%
# Load our genotype file in hapmap format (note: header = F)
myG <- read.csv("gwaspr_myG_hmp.csv", header = F)
# Map + marker Info
myG[1:10,1:11]## V1 V2 V3 V4 V5 V6 V7 V8
## 1 V1 V2 V3 V4 V5 V6 V7 V8
## 2 rs alleles chrom pos strand assembly center protLSID
## 3 Lcu.1GRN.Chr1p853882 A/G 1 853882 <NA> <NA> <NA> <NA>
## 4 Lcu.1GRN.Chr1p854117 G/A 1 854117 <NA> <NA> <NA> <NA>
## 5 Lcu.1GRN.Chr1p854159 A/C 1 854159 <NA> <NA> <NA> <NA>
## 6 Lcu.1GRN.Chr1p854174 C/G 1 854174 <NA> <NA> <NA> <NA>
## 7 Lcu.1GRN.Chr1p870836 A/G 1 870836 <NA> <NA> <NA> <NA>
## 8 Lcu.1GRN.Chr1p870898 C/T 1 870898 <NA> <NA> <NA> <NA>
## 9 Lcu.1GRN.Chr1p870903 G/A 1 870903 <NA> <NA> <NA> <NA>
## 10 Lcu.1GRN.Chr1p871108 A/G 1 871108 <NA> <NA> <NA> <NA>
## V9 V10 V11
## 1 V9 V10 V11
## 2 assayLSID panel QCcode
## 3 <NA> <NA> <NA>
## 4 <NA> <NA> <NA>
## 5 <NA> <NA> <NA>
## 6 <NA> <NA> <NA>
## 7 <NA> <NA> <NA>
## 8 <NA> <NA> <NA>
## 9 <NA> <NA> <NA>
## 10 <NA> <NA> <NA>
# genotrype calls
myG[1:10,12:17]## V12 V13 V14 V15 V16
## 1 V12 V13 V14 V15 V16
## 2 X3156.11_AGL CDC_Asterix_AGL CDC_Cherie_AGL CDC_Glamis_AGL CDC_Gold_AGL
## 3 G A G A G
## 4 G G G A G
## 5 C C C C C
## 6 G G G G G
## 7 G G N G G
## 8 T C N C T
## 9 G G N A G
## 10 A A A A A
## V17
## 1 V17
## 2 CDC_Greenstar_AGL
## 3 A
## 4 G
## 5 A
## 6 C
## 7 A
## 8 C
## 9 G
## 10 A
Phenotype data (myY)
# Load our phenotype file
myY <- read.csv("gwaspr_myY.csv")
myY[1:20,]## Name DTF_Sask_2017 DTF_Nepal_2017 Cotyledon_RedvsYellow
## 1 CDC_Asterix_AGL 54.7 128.0 0
## 2 CDC_Rosie_AGL 59.0 123.3 1
## 3 X3156.11_AGL 60.7 125.3 1
## 4 CDC_Greenstar_AGL 56.7 121.0 0
## 5 CDC_Cherie_AGL 54.3 125.3 1
## 6 CDC_Glamis_AGL 59.0 123.0 0
## 7 CDC_Gold_AGL 54.0 125.3 0
## 8 CDC_Imax_AGL 53.0 128.7 1
## 9 CDC_Impower_AGL 57.0 123.3 0
## 10 CDC_KR.1_AGL 57.0 121.7 1
## 11 CDC_LeMay_AGL 55.7 126.7 0
## 12 CDC_Maxim_AGL 54.3 125.7 1
## 13 CDC_QG.1_AGL 57.7 126.7 NA
## 14 CDC_Red_Rider_AGL 57.0 123.5 1
## 15 CDC_Redcoat_AGL 57.7 126.7 1
## 16 CDC_Redwing_AGL 57.3 128.7 1
## 17 CDC_Robin_AGL 52.0 124.7 1
## 18 CDC_Rosebud_AGL 54.7 121.3 1
## 19 CDC_Rosetown_AGL 57.7 123.7 1
## 20 CDC_Rouleau_AGL 55.3 123.7 1
Covariate data (myCV)
# Load our covariate file
myCV <- read.csv("gwaspr_myCV.csv")
myCV[1:20,]## Name b
## 1 CDC_Asterix_AGL 0.000470
## 2 CDC_Rosie_AGL 0.000335
## 3 X3156.11_AGL 0.000369
## 4 CDC_Greenstar_AGL 0.000521
## 5 CDC_Cherie_AGL 0.000416
## 6 CDC_Glamis_AGL 0.000498
## 7 CDC_Gold_AGL 0.000543
## 8 CDC_Imax_AGL 0.000259
## 9 CDC_Impower_AGL 0.000497
## 10 CDC_KR.1_AGL 0.000746
## 11 CDC_LeMay_AGL 0.000411
## 12 CDC_Maxim_AGL 0.000405
## 13 CDC_QG.1_AGL 0.000468
## 14 CDC_Red_Rider_AGL 0.000251
## 15 CDC_Redcoat_AGL 0.000185
## 16 CDC_Redwing_AGL 0.000225
## 17 CDC_Robin_AGL 0.000461
## 18 CDC_Rosebud_AGL 0.000730
## 19 CDC_Rosetown_AGL 0.000230
## 20 CDC_Rouleau_AGL 0.000348
Run GWAS
Run GWAS on the 3 traits myY
# install.packages("devtools")
# devtools::install_github("jiabowang/GAPIT")
library(GAPIT)
# Run GWAS
myGAPIT <- GAPIT(
# Phenotype data
Y = myY,
# Genotype data
G = myG,
# Set PCA number
PCA.total = 4,
# Select Models
model = c("GLM","MLM","MLMM","FarmCPU","BLINK") )GWAS with Covariate
Run GWAS on the DTF_Sask_2017 trait with b
as a covariate.
# Prep data
myY2 <- myY[,c("Name","DTF_Sask_2017")]
# Rename the trait to be rerun with a covariate
colnames(myY2)[2] <- "DTF_Sask_2017_b"
# Run GWAS with a covariate
myGAPIT <- GAPIT(
# Phenotype data
Y = myY2,
# Genotype data
G = myG,
# Covariate data
CV = myCV,
# Set PCA number
PCA.total = 0,
# Select Models
model = c("GLM","MLM","MLMM","FarmCPU","BLINK") )