Creating and Manipulating gtypes Objects

Eric Archer

2020-02-23

Raw data

It is easiest to load raw genotype data from the disk if it is available as a text file, usually in comma-delimited (.csv) format. The standard R functions read.table or read.csv can be used to accomplish this. However, in strataG, the readGenData function has been provided for .csv files, which is a wrapper for read.csv that sets commonly used values for missing data and removes blank lines.

gen.data <- readGenData("msats.csv")
## Warning in data.table::fread(file = file, header = TRUE, na.strings =
## na.strings, : na.strings[4]==" " consists only of whitespace, ignoring.
## strip.white==TRUE (default) and "" is present in na.strings, so any number of
## spaces in string columns will already be read as <NA>.
str(gen.data)
## 'data.frame':    126 obs. of  12 variables:
##  $ ids    : chr  "4495" "4496" "4498" "5814" ...
##  $ strata : chr  "Offshore.North" "Offshore.North" "Offshore.North" "Offshore.North" ...
##  $ D11t.1 : chr  "133" "137" "133" "135" ...
##  $ D11t.2 : chr  "133" "141" "133" "139" ...
##  $ EV37.1 : chr  NA NA "220" "210" ...
##  $ EV37.2 : chr  NA NA "220" "226" ...
##  $ EV94.1 : chr  NA "243" "245" "251" ...
##  $ EV94.2 : chr  NA "251" "265" "265" ...
##  $ Ttr11.1: chr  "211" NA "209" "209" ...
##  $ Ttr11.2: chr  "211" NA "211" "209" ...
##  $ Ttr34.1: chr  "185" "189" "189" "185" ...
##  $ Ttr34.2: chr  "191" "189" "189" "187" ...
##  - attr(*, ".internal.selfref")=<externalptr>

For sequence data stored in FASTA format, the read.fasta function is available, which is a wrapper for the read.dna function in the ape package with standard FASTA arguments set. This will create a DNAbin object in the workspace:

fname <- system.file("extdata/dolph.seqs.fasta", package = "strataG")
x <- read.fasta(fname) 
x
## 126 DNA sequences in binary format stored in a list.
## 
## All sequences of same length: 402 
## 
## Labels:
## 4495
## 4496
## 4498
## 5814
## 5815
## 5816
## ...
## 
## Base composition:
##     a     c     g     t 
## 0.301 0.229 0.129 0.341 
## (Total: 50.65 kb)

For sequences stored in other formats, read.dna should be used directly.

Construction

For most functions in strataG, you will need to load your data into a gtypes object. A gtypes object is an R S4 class with several slots that are fully described in ?gtypes.
The easiest way to create a gtypes object is with the df2gtypes() function. This function assumes that you have a matrix or data.frame with columns for individual ids, stratification, and locus data. You then specify the columns in the data.frame where this information can be found. df2gtypes() can be used for data with multiple alleles per locus, like this:

# create a single data.frame with the msat data and stratification
msats.merge <- merge(dolph.strata, dolph.msats, all.y = TRUE, description = date())
str(msats.merge)
## 'data.frame':    126 obs. of  14 variables:
##  $ id     : chr  "18650" "18651" "18652" "18653" ...
##  $ dLoop  : chr  "Hap.06" "Hap.14" "Hap.23" "Hap.24" ...
##  $ broad  : chr  "Offshore" "Offshore" "Offshore" "Offshore" ...
##  $ fine   : chr  "Offshore.South" "Offshore.South" "Offshore.South" "Offshore.South" ...
##  $ D11t.1 : chr  "131" "137" "131" "133" ...
##  $ D11t.2 : chr  "133" "143" "133" "139" ...
##  $ EV37.1 : chr  "212" "200" "212" "202" ...
##  $ EV37.2 : chr  "222" "228" "218" "220" ...
##  $ EV94.1 : chr  "263" "249" "249" "229" ...
##  $ EV94.2 : chr  "265" "251" "251" "245" ...
##  $ Ttr11.1: chr  "197" "197" "211" "197" ...
##  $ Ttr11.2: chr  "209" "197" "213" "215" ...
##  $ Ttr34.1: chr  "185" "185" "185" "189" ...
##  $ Ttr34.2: chr  "187" "187" "191" "195" ...
# create the gtypes object
msats.fine <- df2gtypes(msats.merge, ploidy = 2, id.col = 1, strata.col = 3, loc.col = 5)

…or for haploid data, like this:

data(dolph.seqs)

seq.df <- dolph.strata[ c("id", "broad", "id")]
colnames(seq.df)[3] <- "D-loop"
dl.g <- df2gtypes(seq.df, ploidy = 1, sequences = dolph.seqs)
dl.g
## 
## <<< gtypes created on 2020-02-23 16:30:25 >>>
## 
## Contents: 126 samples, 1 locus, 2 strata
## 
## Strata summary:
##    stratum num.ind num.missing num.haplotypes
## 1  Coastal      68           0             68
## 2 Offshore      58           0             58
## 
## Sequence summary:
##    locus num.seqs mean.length mean.num.ns mean.num.indels
## 1 D-loop      126         402           0               0

Note that since each sequence in dolph.seqs is for a given individual, the num.ind and num.haplotypes values are the same for both strata. In order to convert the sequences to unique haplotypes, use the labelHaplotypes() function:

dl.haps <- labelHaplotypes(dl.g)
dl.haps
## 
## <<< gtypes created on 2020-02-23 16:30:25 >>>
## 
## Contents: 126 samples, 1 locus, 2 strata
## Other info: haps.unassigned
## 
## Strata summary:
##    stratum num.ind num.missing num.haplotypes
## 1  Coastal      68           0              5
## 2 Offshore      58           0             29
## 
## Sequence summary:
##    locus num.seqs mean.length mean.num.ns mean.num.indels
## 1 D-loop       33         402           0               0

sequence2gtypes - Convert DNA sequences

The sequence2gtypes() function creates an unstratified gtype object with just a set of DNA sequences:

## 
## <<< gtypes created on 2020-02-23 16:30:26 >>>
## 
## Contents: 33 samples, 1 locus, 1 stratum
## 
## Strata summary:
##   stratum num.ind num.missing num.haplotypes
## 1 Default      33           0             33
## 
## Sequence summary:
##   locus num.seqs mean.length mean.num.ns mean.num.indels
## 1 gene1       33         402           0               0

If you have a vector that identifies strata designations for the sequences, that can be supplied as well:

## 
## <<< dLoop: fine-scale stratification >>>
## 
## Contents: 126 samples, 1 locus, 3 strata
## 
## Strata summary:
##          stratum num.ind num.missing num.haplotypes
## 1        Coastal      68           0             68
## 2 Offshore.North      40           0             40
## 3 Offshore.South      18           0             18
## 
## Sequence summary:
##   locus num.seqs mean.length mean.num.ns mean.num.indels
## 1 dLoop      126         402           0               0

Note that stratification is generally provided for individuals, thus if you want to stratify the resulting gtypes object from sequence2gtypes(), one sequence for each individual should be provided, rather than just a set of unique haplotypes.

Conversions from other packages.

THere are conversion functions for data objects from several other popular packages in R, such as adegenet(genind), pegas(loci), and phangorn(phydat).

## Loading required package: ade4
## 
##    /// adegenet 2.1.2 is loaded ////////////
## 
##    > overview: '?adegenet'
##    > tutorials/doc/questions: 'adegenetWeb()' 
##    > bug reports/feature requests: adegenetIssues()
## /// GENIND OBJECT /////////
## 
##  // 4 individuals; 3 loci; 9 alleles; size: 6.5 Kb
## 
##  // Basic content
##    @tab:  4 x 9 matrix of allele counts
##    @loc.n.all: number of alleles per locus (range: 2-4)
##    @loc.fac: locus factor for the 9 columns of @tab
##    @all.names: list of allele names for each locus
##    @ploidy: ploidy of each individual  (range: 2-2)
##    @type:  codom
##    @call: df2genind(X = df, ncode = 1, ploidy = 2)
## 
##  // Optional content
##    - empty -
## 
## <<< gtypes created on 2020-02-23 16:30:26 >>>
## 
## Contents: 4 samples, 3 loci, 1 stratum
## Other info: genind
## 
## Strata summary:
##   stratum num.ind num.missing num.alleles
## 1 Default       4   0.3333333           3

Accessor functions

There are several functions for getting basic information from a gtypes object (see ?accessors):

Some functions are available for modifying values in the object as well, such as:

Subsetting/Indexing

A gtypes object can be subset using the standard R ‘[’ indexing operation, with three slots: [i, j, k]. The first (i) specifies the desired individuals, the second (j) is the loci to return, and the third (k) is the strata. All standard R indexing operations involving numerical, character, or logical vectors work for each argument. For example, to return 10 random individuals:

sub.msats <- msats.fine[sample(getNumInd(msats.fine), 10), , ]
sub.msats
## 
## <<< gtypes created on 2020-02-23 16:30:25 >>>
## 
## Contents: 10 samples, 5 loci, 2 strata
## 
## Strata summary:
##    stratum num.ind num.missing num.alleles
## 1  Coastal       5           0         3.4
## 2 Offshore       5           0         6.4

…or to return specific loci:

sub.msats <- sub.msats[, c("D11t", "EV37", "TV7"), ]
sub.msats
## 
## <<< gtypes created on 2020-02-23 16:30:25 >>>
## 
## Contents: 10 samples, 2 loci, 2 strata
## 
## Strata summary:
##    stratum num.ind num.missing num.alleles
## 1  Coastal       5           0         2.5
## 2 Offshore       5           0         6.5

…or some loci in a specific stratum:

sub.msats <- msats.fine[, c("Ttr11", "D11t"), "Coastal"]
sub.msats
## 
## <<< gtypes created on 2020-02-23 16:30:25 >>>
## 
## Contents: 68 samples, 2 loci, 1 stratum
## 
## Strata summary:
##   stratum num.ind num.missing num.alleles
## 1 Coastal      68         0.5         3.5

Summary

Several functions have been defined for gtypes, that provide summaries for individuals (summarizeInds()), loci (summarizeLoci()), and sequences (summarizeSeqs()):

summarizeLoci(msats.fine)
##   locus num.genotyped num.missing prop.genotyped num.alleles allelic.richness
## 1  D11t           125           1      0.9920635          12       0.09600000
## 2  EV37           119           7      0.9444444          22       0.18487395
## 3  EV94           125           1      0.9920635          15       0.12000000
## 4 Ttr11           125           1      0.9920635           9       0.07200000
## 5 Ttr34           126           0      1.0000000          10       0.07936508
##   prop.unique.alleles exptd.het obsvd.het
## 1          0.03200000 0.7468273 0.6984127
## 2          0.02521008 0.8270751 0.6587302
## 3          0.01600000 0.8304900 0.7698413
## 4          0.02400000 0.7953414 0.6984127
## 5          0.01587302 0.8144248 0.6984127
summarizeInds(msats.fine)
##        id  stratum num.loci.genotyped num.loci.missing.genotypes
## 1   23945  Coastal                  5                          0
## 2   25503  Coastal                  5                          0
## 3   25509  Coastal                  5                          0
## 4   40915  Coastal                  5                          0
## 5   40916  Coastal                  4                          1
## 6   41538  Coastal                  5                          0
## 7   41539  Coastal                  5                          0
## 8   41540  Coastal                  5                          0
## 9   41578  Coastal                  5                          0
## 10  41579  Coastal                  4                          1
## 11  41819  Coastal                  5                          0
## 12  41820  Coastal                  5                          0
## 13  41821  Coastal                  5                          0
## 14  41822  Coastal                  5                          0
## 15  42192  Coastal                  4                          1
## 16  42193  Coastal                  4                          1
## 17  44718  Coastal                  5                          0
## 18  44719  Coastal                  5                          0
## 19  44720  Coastal                  5                          0
## 20  44721  Coastal                  5                          0
## 21  45229  Coastal                  5                          0
## 22  45230  Coastal                  5                          0
## 23  45231  Coastal                  5                          0
## 24  45232  Coastal                  5                          0
## 25  45233  Coastal                  5                          0
## 26  45234  Coastal                  5                          0
## 27  45236  Coastal                  5                          0
## 28  45237  Coastal                  4                          1
## 29  49095  Coastal                  5                          0
## 30  51981  Coastal                  4                          1
## 31  51982  Coastal                  5                          0
## 32  78033  Coastal                  5                          0
## 33  78034  Coastal                  5                          0
## 34  78035  Coastal                  5                          0
## 35  78036  Coastal                  5                          0
## 36  78037  Coastal                  5                          0
## 37  78038  Coastal                  5                          0
## 38  78039  Coastal                  5                          0
## 39  78040  Coastal                  5                          0
## 40  78041  Coastal                  5                          0
## 41  78042  Coastal                  5                          0
## 42  78043  Coastal                  5                          0
## 43  78044  Coastal                  5                          0
## 44  78045  Coastal                  5                          0
## 45  78046  Coastal                  5                          0
## 46  78047  Coastal                  5                          0
## 47  78048  Coastal                  5                          0
## 48  78049  Coastal                  5                          0
## 49  78050  Coastal                  5                          0
## 50  78051  Coastal                  5                          0
## 51  78052  Coastal                  5                          0
## 52  78053  Coastal                  5                          0
## 53  78054  Coastal                  5                          0
## 54  78055  Coastal                  5                          0
## 55  78056  Coastal                  5                          0
## 56  78057  Coastal                  5                          0
## 57  78058  Coastal                  5                          0
## 58  78059  Coastal                  5                          0
## 59  78060  Coastal                  5                          0
## 60  78061  Coastal                  5                          0
## 61  78062  Coastal                  5                          0
## 62  78063  Coastal                  5                          0
## 63  78064  Coastal                  5                          0
## 64  78065  Coastal                  5                          0
## 65  78066  Coastal                  5                          0
## 66  78067  Coastal                  5                          0
## 67  78068  Coastal                  5                          0
## 68  78069  Coastal                  5                          0
## 69  18650 Offshore                  5                          0
## 70  18651 Offshore                  5                          0
## 71  18652 Offshore                  5                          0
## 72  18653 Offshore                  5                          0
## 73  18654 Offshore                  5                          0
## 74  18655 Offshore                  5                          0
## 75  23792 Offshore                  5                          0
## 76  23793 Offshore                  5                          0
## 77  23794 Offshore                  5                          0
## 78  23801 Offshore                  5                          0
## 79  25182 Offshore                  5                          0
## 80  25184 Offshore                  5                          0
## 81  25185 Offshore                  5                          0
## 82  25186 Offshore                  5                          0
## 83  25469 Offshore                  5                          0
## 84  25470 Offshore                  5                          0
## 85  25471 Offshore                  5                          0
## 86  26304 Offshore                  5                          0
## 87  26305 Offshore                  5                          0
## 88  26310 Offshore                  5                          0
## 89  26316 Offshore                  5                          0
## 90  26317 Offshore                  5                          0
## 91  26318 Offshore                  5                          0
## 92  26320 Offshore                  5                          0
## 93  31888 Offshore                  5                          0
## 94  41757 Offshore                  5                          0
## 95  41758 Offshore                  5                          0
## 96  41759 Offshore                  5                          0
## 97   4495 Offshore                  3                          2
## 98   4496 Offshore                  3                          2
## 99   4498 Offshore                  5                          0
## 100 50742 Offshore                  5                          0
## 101 50743 Offshore                  5                          0
## 102 50744 Offshore                  5                          0
## 103 50745 Offshore                  5                          0
## 104 50746 Offshore                  5                          0
## 105 51382 Offshore                  5                          0
## 106 51383 Offshore                  5                          0
## 107 51384 Offshore                  5                          0
## 108  5814 Offshore                  5                          0
## 109  5815 Offshore                  5                          0
## 110  5816 Offshore                  5                          0
## 111  5817 Offshore                  5                          0
## 112  5818 Offshore                  5                          0
## 113  6151 Offshore                  5                          0
## 114  6153 Offshore                  5                          0
## 115  6290 Offshore                  5                          0
## 116 74959 Offshore                  5                          0
## 117 74960 Offshore                  5                          0
## 118 74961 Offshore                  5                          0
## 119 74962 Offshore                  5                          0
## 120 74963 Offshore                  5                          0
## 121 74964 Offshore                  5                          0
## 122 74965 Offshore                  5                          0
## 123 74966 Offshore                  5                          0
## 124 78530 Offshore                  5                          0
## 125 78531 Offshore                  5                          0
## 126 78532 Offshore                  5                          0
##     pct.loci.missing.genotypes pct.loci.homozygous
## 1                          0.0                 0.4
## 2                          0.0                 0.6
## 3                          0.0                 0.8
## 4                          0.0                 0.6
## 5                          0.2                 0.0
## 6                          0.0                 0.4
## 7                          0.0                 0.6
## 8                          0.0                 0.0
## 9                          0.0                 0.0
## 10                         0.2                 0.2
## 11                         0.0                 0.0
## 12                         0.0                 0.2
## 13                         0.0                 0.8
## 14                         0.0                 0.6
## 15                         0.2                 0.4
## 16                         0.2                 0.0
## 17                         0.0                 0.6
## 18                         0.0                 0.2
## 19                         0.0                 0.2
## 20                         0.0                 0.2
## 21                         0.0                 0.4
## 22                         0.0                 0.0
## 23                         0.0                 0.6
## 24                         0.0                 0.6
## 25                         0.0                 0.2
## 26                         0.0                 0.2
## 27                         0.0                 0.6
## 28                         0.2                 0.2
## 29                         0.0                 0.4
## 30                         0.2                 0.6
## 31                         0.0                 0.4
## 32                         0.0                 0.0
## 33                         0.0                 0.0
## 34                         0.0                 0.2
## 35                         0.0                 1.0
## 36                         0.0                 0.4
## 37                         0.0                 0.2
## 38                         0.0                 0.8
## 39                         0.0                 0.0
## 40                         0.0                 0.4
## 41                         0.0                 0.0
## 42                         0.0                 0.2
## 43                         0.0                 0.6
## 44                         0.0                 0.2
## 45                         0.0                 0.4
## 46                         0.0                 0.4
## 47                         0.0                 0.0
## 48                         0.0                 0.2
## 49                         0.0                 0.4
## 50                         0.0                 0.4
## 51                         0.0                 0.6
## 52                         0.0                 0.4
## 53                         0.0                 0.2
## 54                         0.0                 0.2
## 55                         0.0                 0.8
## 56                         0.0                 0.4
## 57                         0.0                 0.2
## 58                         0.0                 0.2
## 59                         0.0                 0.8
## 60                         0.0                 0.6
## 61                         0.0                 0.4
## 62                         0.0                 0.4
## 63                         0.0                 0.2
## 64                         0.0                 0.6
## 65                         0.0                 0.4
## 66                         0.0                 0.6
## 67                         0.0                 0.4
## 68                         0.0                 0.4
## 69                         0.0                 0.0
## 70                         0.0                 0.2
## 71                         0.0                 0.0
## 72                         0.0                 0.0
## 73                         0.0                 0.2
## 74                         0.0                 0.0
## 75                         0.0                 0.0
## 76                         0.0                 0.2
## 77                         0.0                 0.2
## 78                         0.0                 0.0
## 79                         0.0                 0.0
## 80                         0.0                 0.4
## 81                         0.0                 0.0
## 82                         0.0                 0.4
## 83                         0.0                 0.0
## 84                         0.0                 0.4
## 85                         0.0                 0.0
## 86                         0.0                 0.2
## 87                         0.0                 0.6
## 88                         0.0                 0.2
## 89                         0.0                 0.2
## 90                         0.0                 0.2
## 91                         0.0                 0.2
## 92                         0.0                 0.0
## 93                         0.0                 0.0
## 94                         0.0                 0.4
## 95                         0.0                 0.2
## 96                         0.0                 0.2
## 97                         0.4                 0.4
## 98                         0.4                 0.2
## 99                         0.0                 0.6
## 100                        0.0                 0.6
## 101                        0.0                 0.2
## 102                        0.0                 0.0
## 103                        0.0                 0.2
## 104                        0.0                 0.2
## 105                        0.0                 0.6
## 106                        0.0                 0.0
## 107                        0.0                 0.6
## 108                        0.0                 0.2
## 109                        0.0                 0.6
## 110                        0.0                 0.0
## 111                        0.0                 0.2
## 112                        0.0                 0.0
## 113                        0.0                 0.0
## 114                        0.0                 0.0
## 115                        0.0                 0.0
## 116                        0.0                 0.0
## 117                        0.0                 0.4
## 118                        0.0                 0.0
## 119                        0.0                 0.0
## 120                        0.0                 0.4
## 121                        0.0                 0.0
## 122                        0.0                 0.0
## 123                        0.0                 0.2
## 124                        0.0                 0.2
## 125                        0.0                 0.4
## 126                        0.0                 0.0

Stratifying samples

You can specify the stratification scheme when creating a gtypes object as in the examples above. Once a gtypes object has been created, you can also change the stratification scheme by either supplying a new vector for the @strata slot:

# randomly stratify individuals to two populations
msats <- msats.g
new.strata <- sample(c("Pop1", "Pop2"), getNumInd(msats), rep = TRUE)
names(new.strata) <- getIndNames(msats)
setStrata(msats) <- new.strata
msats
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 2 strata
## Stratification schemes: broad, fine
## 
## Strata summary:
##   stratum num.ind num.missing num.alleles
## 1    Pop1      65           1        12.2
## 2    Pop2      61           1        11.6

or, if there is a stratification scheme data.frame in the @schemes slot, you can use the stratify function to choose a stratification scheme:

# choose "broad" stratification scheme
msats <- stratify(msats, "broad")
msats
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 2 strata
## Stratification schemes: broad, fine
## 
## Strata summary:
##    stratum num.ind num.missing num.alleles
## 1  Coastal      68         1.2         4.8
## 2 Offshore      58         0.8        13.6

You can update the @schemes slot with data.frame like this:

new.schemes <- getSchemes(msats)
new.schemes$ran.pop <- sample(c("Pop5", "Pop6"), getNumInd(msats), rep = TRUE)
setSchemes(msats) <- new.schemes

NOTE: Filling or changing the @schemes slot does not affect the current stratification of the samples. You must then select a new stratification scheme or fill the @strata slot as above.

stratify(msats, "ran.pop")
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 2 strata
## Stratification schemes: broad, fine, ran.pop
## 
## Strata summary:
##   stratum num.ind num.missing num.alleles
## 1    Pop5      59         0.8        11.6
## 2    Pop6      67         1.2        12.2

If some samples should be unstratified (excluded from any stratified analyses), they should have NAs in the appropriate position in the @strata slot. For example:

# unstratify a random 10 samples
x <- getStrata(msats)
x[sample(getIndNames(msats), 10)] <- NA
msats
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 2 strata
## Stratification schemes: broad, fine, ran.pop
## 
## Strata summary:
##    stratum num.ind num.missing num.alleles
## 1  Coastal      68         1.2         4.8
## 2 Offshore      58         0.8        13.6

You can also randomly permute the current stratification scheme using the permuteStrata() function like this:

msats <- stratify(msats, "fine")

# original
msats
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 3 strata
## Stratification schemes: broad, fine, ran.pop
## 
## Strata summary:
##          stratum num.ind num.missing num.alleles
## 1        Coastal      68         1.2         4.8
## 2 Offshore.North      40         0.8        12.6
## 3 Offshore.South      18         0.0        11.0
# permuted
ran.msats <- permuteStrata(msats)
ran.msats
## 
## <<< dolphin msats >>>
## 
## Contents: 126 samples, 5 loci, 3 strata
## Stratification schemes: broad, fine, ran.pop
## 
## Strata summary:
##          stratum num.ind num.missing num.alleles
## 1        Coastal      68         1.4        12.0
## 2 Offshore.North      40         0.4        11.0
## 3 Offshore.South      18         0.2         7.2

NOTE: Only samples assigned to strata are permuted with permuteStrata. Those not assigned (NAs) remain unassigned.

Exporting

The allelic data in a gtypes object can be converted back to a matrix or data frame with as.matrix() and as.data.frame():

gen.mat <- as.matrix(msats)
head(gen.mat)
##      id      stratum          D11t.1 D11t.2 EV37.1 EV37.2 EV94.1 EV94.2 Ttr11.1
## [1,] "18650" "Offshore.South" "131"  "133"  "212"  "222"  "263"  "265"  "197"  
## [2,] "18651" "Offshore.South" "137"  "143"  "200"  "228"  "249"  "251"  "197"  
## [3,] "18652" "Offshore.South" "131"  "133"  "212"  "218"  "249"  "251"  "211"  
## [4,] "18653" "Offshore.South" "133"  "139"  "202"  "220"  "229"  "245"  "197"  
## [5,] "18654" "Offshore.South" "131"  "135"  "214"  "216"  "249"  "249"  "197"  
## [6,] "18655" "Offshore.South" "131"  "137"  "222"  "254"  "243"  "255"  "207"  
##      Ttr11.2 Ttr34.1 Ttr34.2
## [1,] "209"   "185"   "187"  
## [2,] "197"   "185"   "187"  
## [3,] "213"   "185"   "191"  
## [4,] "215"   "189"   "195"  
## [5,] "211"   "185"   "187"  
## [6,] "211"   "183"   "193"

By default, this function splits each allele into its own column. One can make a matrix with one locus per column and alleles separated by a specified character by setting the one.col argument to TRUE:

gen.mat <- as.matrix(msats, one.col = TRUE)
head(gen.mat)
##      id      stratum          D11t      EV37      EV94      Ttr11     Ttr34    
## [1,] "18650" "Offshore.South" "131/133" "212/222" "263/265" "197/209" "185/187"
## [2,] "18651" "Offshore.South" "137/143" "200/228" "249/251" "197/197" "185/187"
## [3,] "18652" "Offshore.South" "131/133" "212/218" "249/251" "211/213" "185/191"
## [4,] "18653" "Offshore.South" "133/139" "202/220" "229/245" "197/215" "189/195"
## [5,] "18654" "Offshore.South" "131/135" "214/216" "249/249" "197/211" "185/187"
## [6,] "18655" "Offshore.South" "131/137" "222/254" "243/255" "207/211" "183/193"

The contents of a gtypes object can be written to a file with the writeGtypes() function. This will write a .csv file with the allelic information and a .fasta file for any sequence data if it exists.