reassignAlleles - Correct allele calls based on a personalized genotype

Description¶

reassignAlleles uses a subject-specific genotype to correct correct preliminary allele assignments of a set of sequences derived from a single subject.

Usage¶

reassignAlleles(
data,
genotype_db,
v_call = "v_call",
seq = "sequence_alignment",
method = "hamming",
path = NA,
keep_gene = c("gene", "family", "repertoire")
)

Arguments¶

data

data.frame containing V allele calls from a single subject and the sample IMGT-gapped V(D)J sequences under seq.

genotype_db

vector of named nucleotide germline sequences matching the calls detailed in allele_calls and personalized to the subject

v_call

name of the column in data with V allele calls. Default is v_call.

seq

name of the column in data with the aligned, IMGT-numbered, V(D)J nucleotide sequence. Default is SEQUENCE_IMGT

method

method to use when realigning sequences to the genotype_db sequences. Currently, only "hamming" (for Hamming distance) is implemented.

path

directory containing the tool used in the realignment method, if needed. Hamming distance does not require a path to a tool.

keep_gene

string indicating if the gene ("gene"), family ("family") or complete repertoire ("repertoire") assignments should be performed. Use of "gene" increases speed by minimizing required number of alignments, as gene level assignments will be maintained when possible.

Value¶

A modified input data.frame containing the best allele call from among the sequences listed in genotype_db in the v_call_genotyped column.

Details¶

In order to save time, initial gene assignments are preserved and the allele calls are chosen from among those provided in genotype_db, based on a simple alignment to the sample sequence.

Examples¶

# Extract the database sequences that correspond to the genotype
genotype_db <- genotypeFasta(SampleGenotype, SampleGermlineIGHV, novel=SampleNovel)

# Use the personalized genotype to determine corrected allele assignments
output_db <- reassignAlleles(AIRRDb, genotype_db, v_call="v_call",
seq="sequence_alignment")