README.md

title: "Introduction to the oc2bioc package" author: - name: Vincent Carey affiliation: Channing Division of Network Medicine, Brigham and Women's Hospital email: stvjc@channing.harvard.edu package: oc2bioc output: BiocStyle::html_document abstract: | This package defines simple interfaces between OpenCRAVAT and Bioconductor vignette: | %\VignetteIndexEntry{Introduction to the oc2bioc package} %\VignetteEngine{knitr::rmarkdown} %\VignetteEncoding{UTF-8} bibliography: oc2bioc.bib

```{r setup,echo=FALSE} suppressPackageStartupMessages({ library(oc2bioc) library(curatedTCGAData) })


# Introduction

We propose a bidirectional interface between Bioconductor (@Huber2015) and OpenCRAVAT (@Pagel2020).

## Enumerating OpenCRAVAT "modules"

We aim for an interactively searchable table along the lines of

![filtered table of modules](filt.png)

We use the `open-cravat` python modules (installed with oc2bioc,
via the basilisk protocol) to obtain the listing of all modules.
This listing is managed in an S4 class instance:

```{r doo}
library(oc2bioc)
ms = populate_module_set()
ms

An as.data.frame method is available. ```{r lkh} dim(as.data.frame(ms))


Use `DT::datatable` with the data.frame instance to obtain the
searchable table depicted above.

## Single-variant queries

The `queryOC` function authenticates to the OpenCRAVAT project's server
and uses the RESTful API to resolve queries.  If username and
password are not supplied, environment variables are queried
to obtain these.

Here's an illustration of how this works.  This chunk
will not run unless an OpenCRAVAT username and
password are supplied as the first two arguments.
```{r try1, eval=FALSE}
var_in_tx = queryOC([uname], [passwd], chr="chr7", pos="140753336", 
   ref="A", alt="T", 
   annotator=c("chasmplus_BRCA", "pubmed", "segway_breast"))

The response to this request (made on 6 Sept 2020 and saved) is: ```{r lkvar} var_in_tx names(vv <- httr::content(var_in_tx))

The ChasmPlus result looks like
```{r lkcpl}
vv$chasmplus_BRCA

Another illustration with a variant in a long non-coding RNA (@Suvanto2020) is:

> nonco_var = queryOC(,[username], [passwd], chr="chr15", pos="50394581", ref="G", alt="C",
+    annotator=c("chasmplus_BRCA", "pubmed", "segway_breast",
+       "dbsnp", "ncrna", "gtex", "phdsnpg"))
> nonco_var
Response [https://run.opencravat.org/submit/annotate?chrom=chr15&pos=50394581&ref_base=G&alt_base=C&annotators=chasmplus_BRCA,pubmed,segway_breast,dbsnp,ncrna,gtex,phdsnpg]
  Date: 2020-10-09 19:12
  Status: 200
  Content-Type: application/json; charset=utf-8
  Size: 416 B
> library(httr)
0/0 packages newly attached/loaded, see sessionInfo() for details.
> names(content(nonco_var))
[1] "ncrna"          "pubmed"         "gtex"           "segway_breast" 
[5] "chasmplus_BRCA" "dbsnp"          "phdsnpg"        "crx" 

There is no novel content in the fields, except the position is noted as Quiescent in the segway_breast resources, and the dbSNP id (rs28489579) is returned.

Working with a local deployment of OpenCRAVAT

Using the REST API

When a local deployment is running, for example via oc gui, queryOC can be used with appropriate settings of baseURL to direct queries to locally installed annotators.

Acquiring a collection of variants

We'll use the adrenocortical carcinoma data from TCGA to obtain a set of variants. These are available as a GRanges gr38 in the oc2bioc package. The codes to generate this are presented without evaluation here:

```{r lklkacc,eval=FALSE} library(curatedTCGAData) suppressMessages({ acc = curatedTCGAData("ACC", "Mutation", dry.run=FALSE, verbose=FALSE) }) mut = experiments(acc)[[1]] mut

The "assays" available record much information about the
specific variants; we only need REF/ALT codes.
```{r theass,eval=FALSE}
assayNames(mut)[c(1,7:9)]

The addresses of the variants are available after coercing the RaggedArray instance to a GRangesList; this is simplified to a GRanges with unlist. ```{r geta,eval=FALSE} gr = unlist(as(mut, "GRangesList")) dim(mcols(gr)) head(gr[,1:3],3)

Multibase variants are present.  We'll
confine attention to single-nucleotide variants (SNV).
```{r getsnv, eval=FALSE}
table(width(gr))[1:6]
gr = gr[width(gr)==1]
We'll want the variants in GRCh38 coordinates.
```{r doma,eval=FALSE}
seqlevels(gr) = paste0("chr", seqlevels(gr))
gr38 = unlist(rtracklayer::liftOver(gr, oc2bioc::ch19to38))
genome(gr38) = "hg38" # UCSC terminology
head(gr38[,1:3],3)
length(gr38)
length(unique(gr38))

Transforming to a POST-able file, via data.frame

```{r mm} mtb = make_oc_POSTable(gr38) # already remapped head(mtb)

Use code like

write.table(mtb, file="/tmp/abc.txt", sep="\t", col.names=FALSE, row.names=FALSE, quote=FALSE)

to create a file that can be ingested by OpenCRAVAT.

### Submitting the multivariant query for local annotation

Once the POSTable table has been written to a file, call `run_oc_req`
with a `url` appropriate to your system, as in the following:

myrun = run_oc_req(url="http://0.0.0.0:8080/submit/submit", postfile="/tmp/abc.txt", annotators=c("clinvar", "segway_lung"), reports=c("text", "vcf"), assembly="hg38", note="test run")

The object `myrun` will be an R representation of a python dictionary
with element `r`.  This can be interrogated as `myrun$r$json()` to
get information about the run.

str(myrun$r$json()) List of 14 $ orig_input_fname : chr "abc.txt" $ assembly : chr "hg38" $ note : chr "test run" $ db_path : chr "" $ viewable : logi FALSE $ reports : chr [1:2] "text" "vcf" $ annotators : chr [1:2] "clinvar" "segway_lung" $ annotator_version : chr "" $ open_cravat_version: chr "" $ num_input_var : chr "" $ submission_time : chr "2020-09-25T14:15:20.625643" $ id : chr "200925-141520" $ run_name : chr "abc.txt" $ status :List of 1 ..$ status: chr "Submitted"

Of crucial significance here is the `id` component.  This will be
used to find the annotations computed by OpenCRAVAT.

An example annotation result is shipped with the package
as `crx_demo`.
```{r lkde}
data(crx_demo)
names(crx_demo)
nonsyn = which(crx_demo[,10]!="SYN")
head(crx_demo[nonsyn,c(2,3,8:10)])

Retrieving locally generated annotation results

Direct querying of annotator SQLite

Local deployments of OpenCRAVAT will have SQLite databases corresponding to the installed annotators. The oc2bioc package includes utilities for identifying and querying these.

Here's an example. Segway's lung data is actually all based on fetal lung tissue.

> list_local_annotators()
[1] "clinvar"       "genehancer"    "segway_lung"   "segway_muscle"
> lcon = connect_local_annotator("segway_lung")
> dbListTables(lcon)
 [1] "chr1"                    "chr10"                  
 [3] "chr11"                   "chr12"                  
 [5] "chr12_GL877875v1_alt"    "chr13"                  
...
> lcon %>% tbl("chr1") %>% glimpse()
Rows: ??
Columns: 5
Database: sqlite 3.30.1 [/home/stvjc/.local/lib/python3.8/site-packages/cravat/modules/annotators/segway_lung/data/segway_lung.sqlite]
$ bin    <int> 585, 585, 585, 585, 585, 585, 585, 585, 585, 585, 585, 585, 58…
$ start  <int> 11000, 13000, 13500, 14800, 15100, 54400, 54700, 55700, 79100,…
$ end    <int> 13000, 13500, 14800, 15100, 16100, 54700, 55700, 56000, 79300,…
$ tissue <chr> "FETAL_LUNG", "FETAL_LUNG", "FETAL_LUNG", "FETAL_LUNG", "FETAL…
$ state  <chr> "11_Quiescent", "9_Quiescent", "11_Quiescent", "9_Quiescent", …

Appendix: Ontology resources

Sequence Ontology (SO) is used to label and group variants by structural or functional type. We noted abbreviations for SO terms in the crx_demo file and did not see a conventional mapping for these. The mapping was extracted from JSON found in cravat_util.py. ```{r lksom} head(SO_map)


To help interpret the SO terms, we include a snapshot of the SO that retains
the graphical structure of relationships among terms.  A view of variant-related
concepts can be plotted using tools in the ontologyIndex and ontoProc packages.

```{r lksopl}
ontoProc::onto_plot2(SO_onto, na.omit(SO_map[,3])[39:49])

Not all the terms used in OpenCRAVAT are in the display above, and most of the terms in the display are not explicitly used in OpenCRAVAT. The display is here to orient readers to the SO concepts.

References



vjcitn/oc2bioc documentation built on Aug. 11, 2021, 1:04 p.m.