adding a comment about the PATH variable so that can found the NCBI_SRA tools

diff --git a/datasets/get_OXYchIPseq-files.sh b/datasets/get_OXYchIPseq-files.sh
index 400ab2b..599c0dc 100755
--- a/datasets/get_OXYchIPseq-files.sh
+++ b/datasets/get_OXYchIPseq-files.sh
@@ -1,13 +1,14 @@
 #!/bin/bash

-# Tool for download Oxytrichia data from NCBI_SRA
+# Tool for downloading "Oxytrichia" data from NCBI_SRA
 # This script is part of
 # RACS v1.0 (2018/2019) -- Open source tools for Analizing ChIP-Seq data

 # It requires the "NCBI SRA (Sequence Read Archive)" to download the data
 # whcioh can be obtained from	https://github.com/ncbi/sra-tools

-# set PATH to add "SRA toolkit"
+# if it is not part of your PATH, you can use this to add the location
+# where "SRA toolkit" is installed so it can be used to download the NCBI data
 PATH=$PATH:/scratch1/mponce/RESEARCH/Tetrahymena_Ryerson/TOOLS/NCBI_SRA_toolkit/sratoolkit.2.9.6-1-ubuntu64/bin

 #######################################################
@@ -49,3 +50,4 @@ for i in *fastq; do
 	gzip -c $i > $i.gz ;
 done

+