diff --git a/R/gen_tibble.R b/R/gen_tibble.R
index 38eec8e7..eff5275c 100644
--- a/R/gen_tibble.R
+++ b/R/gen_tibble.R
@@ -116,11 +116,42 @@ gen_tibble_bed_rds <- function(x, ...,
 
   indiv_meta <- list(id = bigsnp_obj$fam$sample.ID,
                              population = bigsnp_obj$fam$family.ID)
+  # TODO check if other elements are informative; if they are, bring them over
+
 
   indiv_meta$genotypes <- new_vctrs_bigsnp(bigsnp_obj,
                                            bigsnp_file = bigsnp_path,
                                            indiv_id = bigsnp_obj$fam$sample.ID)
 
+  # transfer some of the fam info to the metadata table if it is not missing (0 is the default missing value)
+  fam_info <- .gt_get_bigsnp(indiv_meta)$fam
+  if(!all(fam_info$paternal.id==0)){
+    indiv_meta$paternal_ID <- fam_info$paternal.id
+    indiv_meta$paternal_ID[indiv_meta$paternal_ID==0]<-NA
+  }
+  if(!all(fam_info$maternal.id==0)){
+    indiv_meta$maternal_ID <- fam_info$maternal.id
+    indiv_meta$maternal_ID[indiv_meta$maternal_ID==0]<-NA
+  }
+  if(!all(fam_info$sex==0)){
+    indiv_meta$sex <-   dplyr::case_match(
+      fam_info$sex,
+      1 ~ "male",
+      2 ~ "female",
+      .default = NA,
+      .ptype = factor(levels = c("female", "male"))
+    )
+  }
+  if(!all(fam_info$affection %in% c(0,-9))){
+  indiv_meta$phenotype <- dplyr::case_match(
+    fam_info$affection,
+    1 ~ "control",
+    2 ~ "case",
+    -9 ~ NA,
+    .default = NA,
+    .ptype = factor(levels = c("control", "case"))
+  )
+  }
   new_gen_tbl <- tibble::new_tibble(
     indiv_meta,
     class = "gen_tbl"
diff --git a/R/gen_tibble_ped.R b/R/gen_tibble_ped.R
index 3401a625..b596a072 100644
--- a/R/gen_tibble_ped.R
+++ b/R/gen_tibble_ped.R
@@ -39,10 +39,10 @@ read.pedfile <- function(file, n, snps, which, split="\t| +", sep=".",
 #  r2 <- as.raw(2)
 #  r3 <- as.raw(3)
 
-  r0 <- 3
-  r1 <- 2
+  r0 <- NA_integer_
+  r1 <- 0
   r2 <- 1
-  r3 <- 0
+  r3 <- 2
 
   ## Input file
   con <- gzfile(file)
diff --git a/R/gt_as_plink.R b/R/gt_as_plink.R
index f4a2f16a..461b5e3f 100644
--- a/R/gt_as_plink.R
+++ b/R/gt_as_plink.R
@@ -1,38 +1,169 @@
 #' Export a `gen_tibble` object to PLINK bed format
 #'
 #' This function exports all the information of a `gen_tibble` object into
-#' a PLINK bed file.
+#' a PLINK bed, ped or raw file (and associated files, i.e. .bim and .fam for .bed;
+#' .fam for .ped).
 #'
 #' @param x a [`gen_tibble`] object
-#' @param bedfile a character string giving the path to output bed file.
+#' @param file a character string giving the path to output file. If left to NULL,
+#' the output file will have the same path and prefix of the backingfile.
+#' @param type one of "bed", "ped" or "raw"
 #' @param overwrite boolean whether to overwrite the file.
-#' @returns TRUE if successful
+#' @returns the path of the saved file
 #' @export
 
 
-gt_as_plink <- function(x, bedfile = NULL,
+gt_as_plink <- function(x, file = NULL, type = c("bed","ped","raw"),
                            overwrite = TRUE){
-  if (is.null(bedfile)){
-    bedfile <- bigstatsr::sub_bk(attr(x$genotypes,"bigsnp")$genotypes$backingfile,".bed")
+  type <- match.arg(type)
+
+  if (is.null(file)){
+    file <- bigstatsr::sub_bk(attr(x$genotypes,"bigsnp")$genotypes$backingfile,paste0(".",type))
+  }
+  if (file_ext(file)!=type){
+    file <- paste0(file,".",type)
   }
-  if (file_ext(bedfile)!="bed"){
-    bedfile <- paste0(bedfile,".bed")
+
+ if (type=="bed"){
+    all_files <- c(file,
+                   bigsnpr::sub_bed(file,".bim"),
+                   bigsnpr::sub_bed(file,".fam")
+                   )
+  } else if (type=="ped"){
+    all_files <- c(file,
+                   gsub(".ped",".fam",file))
+  } else if (type=="raw"){
+    all_files <- file
   }
-  if (file.exists(bedfile)){
+
+  if (any(file.exists(all_files))){
     if (overwrite){
-      file.remove(bedfile)
-      file.remove(bigsnpr::sub_bed(bedfile,".bim"))
-      file.remove(bigsnpr::sub_bed(bedfile,".fam"))
-    } else {
-      stop(bedfile," already exists; remove if first or set 'overwrite' = TRUE")
+      file.remove(all_files[file.exists(all_files)])
+  } else {
+      stop("at least one of", all_files," already exists; remove if first or set 'overwrite' = TRUE")
     }
   }
 
+  if (type == "bed"){
+    gt_write_bed(x, file)
+  } else {
+    gt_write_ped_raw(x,file,type)
+  }
+}
+
+
+gt_write_bed <- function(x, file) {
   bed_path <- bigsnpr::snp_writeBed(attr(x$genotypes,"bigsnp"),
-                        bedfile = bedfile,
+                        bedfile = file,
                         ind.row = vctrs::vec_data(x$genotypes),
                         ind.col = show_loci(x)$big_index)
   # the bim and fam file only contain the original information in the bigSNP object
   # TODO we should update them with the info from the gentibble
   bed_path
 }
+
+
+
+gt_write_ped_raw <- function(x, file, plink_format = c("raw","ped"), chunk_size = 10000){
+
+  # loci information
+  loci <- show_loci(x)
+  # replace missing value with zero
+  loci$allele_alt[is.na(loci$allele_alt)]<-"0"
+
+  # create col names to use in the raw file
+  raw_col_names<- c("FID", "IID", "PAT", "MAT", "SEX", "PHENOTYPE",
+                    paste0(loci$name,"_",toupper(loci$allele_alt),"(/",toupper(loci$allele_ref),")"))
+
+  # create the info for the fam file
+  indiv_meta <- tibble(population = x$population,
+                       id = x$id,
+                       pat = pull_NA(x, "pat"),
+                       mat = pull_NA(x, "mat"),
+                       sex = pull_NA(x, "sex"),
+                       phenotype = pull_NA(x, "phenotype")
+  )
+  # recode some variables
+  indiv_meta$sex<- dplyr::case_match(as.character(indiv_meta$sex),'female'~'2','male'~'1',.default="0")
+  indiv_meta$pat[is.na(indiv_meta$pat)]<-0
+  indiv_meta$mat[is.na(indiv_meta$mat)]<-0
+  indiv_meta$phenotype<-dplyr::case_match(as.character(indiv_meta$phenotype),
+                                          'control'~"1",'case'~"2", .default=indiv_meta$phenotype )
+  indiv_meta$phenotype[is.na(indiv_meta$phenotype)]<--9
+
+  # create chunks
+  n_ind <- nrow(x)
+  chunks <- split(1:n_ind, ceiling(seq_along(1:n_ind)/chunk_size))
+
+  # loop over to write
+  for (i_chunk in seq_len(length(chunks))){
+    chunk <- chunks[[i_chunk]]
+    raw_table <- cbind(indiv_meta[chunk,],
+                       show_genotypes(x[chunk,]))
+
+    # now recode the genotypes with letters if raw
+    if (plink_format=="ped"){
+      for (i in 1:(ncol(raw_table)-6)){
+        raw_table[,i+6]<-recode_genotype(raw_table[,i+6], loci$allele_ref[i], loci$allele_alt[i])
+      }
+    }
+
+    colnames(raw_table) <- raw_col_names
+    # append column names only the first time, when the file does not exist
+    utils::write.table(raw_table,
+                       file=file,
+                       sep = " ",
+                       row.names = FALSE,
+                       col.names=(!file.exists(file) & plink_format=="raw"),
+                       append = file.exists(file),
+                       quote = FALSE)
+
+  }
+
+  ## create info for the map file
+  loci_meta <- show_loci(x)
+  map_file <- paste0(substr(file, 1, nchar(file)-4),".map")
+  map_table <- tibble(chrom = pull_NA(loci_meta,"chromosome"),
+                      id = pull_NA(loci_meta,"name"),
+                      cM = pull_NA(loci_meta,"cM"),
+                      position = pull_NA(loci_meta,"position"))
+  map_table[is.na(map_table)]<-0
+
+  utils::write.table(
+    map_table,
+    file = map_file,
+    row.names = FALSE,
+    col.names = FALSE,
+    quote = FALSE
+  )
+  return(file)
+}
+
+
+# internal function returning either a vector from a given column or NA if it does not exist
+pull_NA <- function(.x, .col_name) {
+  if (.col_name %in% names(.x)){
+    return(.x %>% pull(.col_name))
+  } else {
+    return(rep(NA,nrow(.x)))
+  }
+}
+
+# recode dosage as letter genotypes
+recode_genotype <- function(x, allele_ref, allele_alt){
+  x <-as.character(x)
+  genotypes <- c(paste(allele_ref, allele_ref),
+                 paste(allele_ref, allele_alt),
+                 paste(allele_alt, allele_alt))
+  x <- dplyr::case_match(
+    x,
+    "0" ~ genotypes[1],
+    "1" ~ genotypes[2],
+    "2" ~ genotypes[3]
+  )
+  x[is.na(x)]<-c("0 0")
+  x
+
+}
+
+
diff --git a/inst/extdata/pop_a.bk b/inst/extdata/pop_a.bk
new file mode 100644
index 00000000..57b68c9f
Binary files /dev/null and b/inst/extdata/pop_a.bk differ
diff --git a/inst/extdata/pop_a.ped b/inst/extdata/pop_a.ped
new file mode 100644
index 00000000..a48c2989
--- /dev/null
+++ b/inst/extdata/pop_a.ped
@@ -0,0 +1,5 @@
+pop_a GRC14300079 0 0 1 -9 A A A A G G A A G G T G G G C C T T C C T T G G T T A G T T T T
+pop_a GRC14300142 0 0 1 -9 A A A A G G A A G G G G G G C C T T G C A T G G T T G G C T T T
+pop_a GRC14300159 0 0 1 -9 A A G A A G A A A A T G G G C C T T C C T T G G T T A G T T T T
+pop_a GRC14300286 0 0 1 -9 A A A A G G A A G G G G G G C C T T G C T T G G T T A G C T T T
+pop_a GRC14300305 0 0 1 -9 A A A A A G A A A G T T G G C C T T C C T T G G T T A G T T T T
diff --git a/inst/extdata/pop_a.rds b/inst/extdata/pop_a.rds
new file mode 100644
index 00000000..2710662d
Binary files /dev/null and b/inst/extdata/pop_a.rds differ
diff --git a/man/gt_as_plink.Rd b/man/gt_as_plink.Rd
index f2665bcf..5bbae9d2 100644
--- a/man/gt_as_plink.Rd
+++ b/man/gt_as_plink.Rd
@@ -4,19 +4,23 @@
 \alias{gt_as_plink}
 \title{Export a \code{gen_tibble} object to PLINK bed format}
 \usage{
-gt_as_plink(x, bedfile = NULL, overwrite = TRUE)
+gt_as_plink(x, file = NULL, type = c("bed", "ped", "raw"), overwrite = TRUE)
 }
 \arguments{
 \item{x}{a \code{\link{gen_tibble}} object}
 
-\item{bedfile}{a character string giving the path to output bed file.}
+\item{file}{a character string giving the path to output file. If left to NULL,
+the output file will have the same path and prefix of the backingfile.}
+
+\item{type}{one of "bed", "ped" or "raw"}
 
 \item{overwrite}{boolean whether to overwrite the file.}
 }
 \value{
-TRUE if successful
+the path of the saved file
 }
 \description{
 This function exports all the information of a \code{gen_tibble} object into
-a PLINK bed file.
+a PLINK bed, ped or raw file (and associated files, i.e. .bim and .fam for .bed;
+.fam for .ped).
 }
diff --git a/src/snp_as.cpp b/src/snp_as.cpp
index 18d7c861..2ae71a7e 100644
--- a/src/snp_as.cpp
+++ b/src/snp_as.cpp
@@ -41,8 +41,8 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
   size_t n = macc.nrow();
   size_t m = macc.ncol();
 
-  for (int j = 0; j < m; j++) {
-    for (int i = 0; i < n; i++) {
+  for (unsigned int j = 0; j < m; j++) {
+    for (unsigned int i = 0; i < n; i++) {
       int value = (macc(i,j));
       if (value <3){
         dos_mat(i, j) = value-1; // note that we want the matrix of (dos-1)
@@ -53,10 +53,10 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
     }}
 
   // fill the rest with 0s (should be 1 column max)
-  int m2 = dos_mat.n_cols;
+  size_t m2 = dos_mat.n_cols;
   if (m2 > m) {
     myassert(m2 == (m + 1), ERROR_BUG);
-    for (int i = 0; i < n; i++) {
+    for (unsigned int i = 0; i < n; i++) {
       dos_mat(i, m) = 1;
       na_mat(i, m) = 0;
     }
diff --git a/src/snp_ibs.cpp b/src/snp_ibs.cpp
index 606fca43..d741a2ce 100644
--- a/src/snp_ibs.cpp
+++ b/src/snp_ibs.cpp
@@ -42,8 +42,8 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
   size_t n = macc.nrow();
   size_t m = macc.ncol();
 
-  for (int j = 0; j < m; j++) {
-    for (int i = 0; i < n; i++) {
+  for (unsigned int j = 0; j < m; j++) {
+    for (unsigned int i = 0; i < n; i++) {
       int value = (macc(i,j));
       if (value == 0){
         genotype0(i, j) = 1;
@@ -55,10 +55,10 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
     }}
 
   // fill the rest with 0s (should be 1 column max)
-  int m2 = genotype0.n_cols;
+  size_t m2 = genotype0.n_cols;
   if (m2 > m) {
     myassert(m2 == (m + 1), ERROR_BUG);
-    for (int i = 0; i < n; i++) {
+    for (unsigned int i = 0; i < n; i++) {
       genotype0(i, m) = 0;
       genotype1(i, m) = 0;
       genotype2(i, m) = 0;
diff --git a/src/snp_king.cpp b/src/snp_king.cpp
index 1d51418a..2b8d542f 100644
--- a/src/snp_king.cpp
+++ b/src/snp_king.cpp
@@ -42,8 +42,8 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
   size_t n = macc.nrow();
   size_t m = macc.ncol();
 
-  for (int j = 0; j < m; j++) {
-    for (int i = 0; i < n; i++) {
+  for (unsigned int j = 0; j < m; j++) {
+    for (unsigned int i = 0; i < n; i++) {
       int value = (macc(i,j));
       if (value == 0){
         genotype0(i, j) = 1;
@@ -58,10 +58,10 @@ inline arma::mat FBM_RW2arma(Rcpp::Environment BM) {
     }}
 
   // fill the rest with 0s (should be 1 column max)
-  int m2 = genotype0.n_cols;
+  size_t m2 = genotype0.n_cols;
   if (m2 > m) {
     myassert(m2 == (m + 1), ERROR_BUG);
-    for (int i = 0; i < n; i++) {
+    for (unsigned int i = 0; i < n; i++) {
       genotype0(i, m) = 0;
       genotype1(i, m) = 0;
       genotype2(i, m) = 0;
diff --git a/tests/testthat/test_gen_tibble.R b/tests/testthat/test_gen_tibble.R
index 2cf81aa5..5b2460b0 100644
--- a/tests/testthat/test_gen_tibble.R
+++ b/tests/testthat/test_gen_tibble.R
@@ -14,7 +14,7 @@ test_loci <- data.frame(name=paste0("rs",1:6),
 test_gt <- gen_tibble(x = test_genotypes, loci = test_loci, indiv_meta = test_indiv_meta, quiet = TRUE)
 
 # this also tests show_genotypes and show_loci
-test_that("create gen_tibble from bed",{
+test_that("create gen_tibble from dfs",{
   expect_true(inherits(test_gt,"gen_tbl"))
   # we can extract the genotypes correctly
   extracted_genotypes <- test_gt %>% show_genotypes()
@@ -32,17 +32,6 @@ test_that("create gen_tibble from bed",{
 
 })
 
-# now create it directly from the dfs
-test_that("create gen_tibble from dfs",{
-  test_dfs_gt <- gen_tibble(test_genotypes, indiv_meta = test_indiv_meta,
-             loci = test_loci, quiet = TRUE)
-  # because of the different backing file info, we cannot use identical on the whole object
-  expect_true(identical(show_genotypes(test_gt), show_genotypes(test_dfs_gt)))
-  expect_true(identical(show_loci(test_gt), show_loci(test_dfs_gt)))
-  expect_true(identical(test_gt %>% select(-genotypes),
-                        test_dfs_gt %>% select(-genotypes)))
-})
-
 test_genotypes_c <- rbind(c("1","1","0","1","1","0"),
                           c("2","1","0","0","0","0"),
                           c("2","2","0","0","1","1"))
@@ -81,4 +70,17 @@ test_that("gen_tibble catches invalid alleles",{
 
 })
 
+test_that("gen_tibble from a bed file",{
+  bed_path <- system.file("extdata/pop_a.bed", package = "tidypopgen")
+  pop_a_gt <- gen_tibble(bed_path, quiet=TRUE, backingfile = tempfile())
+  # now read the dosages created by plink when saving in raw format
+  raw_file_pop_a <- read.table(system.file("extdata/pop_a.raw", package = "tidypopgen"), header= TRUE)
+  mat <- as.matrix(raw_file_pop_a[,7:ncol(raw_file_pop_a)])
+  mat <- unname(mat)
+  expect_true(all.equal(mat,show_genotypes(pop_a_gt)))
+  # now read in the ped file
+  ped_path <- system.file("extdata/pop_a.ped", package = "tidypopgen")
+  pop_a_ped_gt <- gen_tibble(ped_path, quiet=TRUE,backingfile = tempfile())
+  all.equal(show_genotypes(pop_a_gt),show_genotypes(pop_a_ped_gt))
 
+})
diff --git a/tests/testthat/test_gt_as_plink.R b/tests/testthat/test_gt_as_plink.R
index c43c1dfd..ca49ecb3 100644
--- a/tests/testthat/test_gt_as_plink.R
+++ b/tests/testthat/test_gt_as_plink.R
@@ -3,7 +3,7 @@ test_indiv_meta <- data.frame (id=c("a","b","c"),
                                population = c("pop1","pop1","pop2"))
 test_genotypes <- rbind(c(1,1,0,1,1,0),
                         c(2,1,0,0,0,0),
-                        c(2,2,0,0,1,1))
+                        c(2,2,0,0,NA,1))
 test_loci <- data.frame(name=paste0("rs",1:6),
                         chromosome=paste0("chr",c(1,1,1,1,2,2)),
                         position=as.integer(c(3,5,65,343,23,456)),
@@ -16,7 +16,7 @@ test_gt <- gen_tibble(x = test_genotypes, loci = test_loci, indiv_meta = test_in
 
 # this also tests show_genotypes and show_loci
 test_that("write a bed file",{
-  bed_path <- gt_as_plink(test_gt, bedfile = paste0(tempfile(),".bed"))
+  bed_path <- gt_as_plink(test_gt, file = paste0(tempfile(),".bed"))
   # now read the file back in
   test_gt2 <- gen_tibble(bed_path, quiet=TRUE)
   ## continue here
@@ -30,5 +30,18 @@ test_that("write a bed file",{
   expect_true(is.na(show_loci(test_gt2)$allele_alt[3]))
 
 
+  # now write it as a ped
+  ped_path <- gt_as_plink(test_gt, file = paste0(tempfile(),".ped"), type = "ped")
+  test_gt3 <- gen_tibble(ped_path, quiet=TRUE)
+  # the gen tibble from the bed and ped should contain the same information
+  expect_true(all.equal(show_loci(test_gt3),show_loci(test_gt2), check.attributes=FALSE))
+  expect_true(all.equal(show_genotypes(test_gt3),show_genotypes(test_gt2)))
+
+  # write it as raw
+  raw_path <- gt_as_plink(test_gt,file=tempfile(),type="raw")
+  raw_file_test <- read.table(raw_path, header= TRUE)
+  mat <- as.matrix(raw_file_test[,7:ncol(raw_file_test)])
+  mat <- unname(mat)
+  expect_true(all.equal(mat,show_genotypes(test_gt)))
 })
 
diff --git a/vignettes/example_clustering_and_dapc.Rmd b/vignettes/example_clustering_and_dapc.Rmd
index 49923c39..8a69afcd 100644
--- a/vignettes/example_clustering_and_dapc.Rmd
+++ b/vignettes/example_clustering_and_dapc.Rmd
@@ -3,7 +3,7 @@ title: "example workflow with tidypopgen"
 output: rmarkdown::html_vignette
         #pdf_document
 vignette: >
-  %\VignetteIndexEntry{example_workflow}
+  %\VignetteIndexEntry{example workflow with tidypopgen}
   %\VignetteEngine{knitr::rmarkdown}
   %\VignetteEncoding{UTF-8}
 ---
diff --git a/vignettes/overview.Rmd b/vignettes/overview.Rmd
index c1fb692e..7d8e3925 100644
--- a/vignettes/overview.Rmd
+++ b/vignettes/overview.Rmd
@@ -367,12 +367,14 @@ write a file in the appropriate format, and return the name of that file on comp
 For example, to export to a PLINK .bed file, we simply use:
 
 ```{r}
-gt_as_plink(example_gt, bedfile =  tempfile("new_bed_"))
+gt_as_plink(example_gt, file =  tempfile("new_bed_"))
 ```
 
 This will also write a .bim and .fam file and save them together with the .bed file. 
 Note that, from the main tibble, only
 on `id`, `population` and `sex` will be preserved in the .fam file.
+It is also possible to write .ped and .raw files by specifying `type="ped"` or
+`type="raw"` in `gt_as_plink()` (see the help page for `gt_as_plink()` for details).
 
 # Merging data