Update file biomart_for_annotation.R

05_Data_Annotation/biomart_for_annotation.R

+# Load required library for using biomaRt
 library(biomaRt)
+
+# Create a connection to the Ensembl database and specify the human gene dataset
 ensembl <- useMart("ensembl", dataset = "hsapiens_gene_ensembl")
+
+# Read data from a CSV file named "mrna.csv" and store it in the "mrna" variable.
 mrna <- read.csv("C:/Users/Emre/Desktop/mrna.csv")
+
+# Extract the gene symbols from the "mrna" data and store them in "gene_list".
 gene_list <- mrna$Gene_symbol
+
+# Display the contents of the "gene_list" variable, which contains the gene symbols.
 gene_list
 
+# Use biomaRt to retrieve the Ensembl gene IDs and external gene names (gene symbols)
+# corresponding to the gene symbols in "gene_list".
 ensembl_ids <- getBM(attributes = c("ensembl_gene_id", "external_gene_name"),
                      filters = "external_gene_name",
                      values = gene_list,
                      mart = ensembl)
 
+# Print the retrieved Ensembl gene IDs and their corresponding gene symbols.
 print(ensembl_ids)
 
+# Load required library for writing data to Excel files
 library(writexl)
-write_xlsx(ensembl_ids, path = "C:/Users/Emre/Desktop/go.csv")
-
 
+# Write the retrieved Ensembl gene IDs and gene symbols to an Excel file named "go.csv".
+write_xlsx(ensembl_ids, path = "C:/Users/Emre/Desktop/go.csv")