updated data format for the `description` column

updated dataset `description` column with a space between `chr{chr}:{position}` and `{ref_base}:{alt_base}` similar to vep-traitgym

README.md

@@ -27,7 +27,7 @@ Description of data columns:
 - `target`: Whether the specified sequence contains a pathogenic mutation.
 - `cds`: Binary track which reports position of first nucleotide in each codon in CDS.
 - `splice`: Binary track which reports position of the 3' end of each exon, indicating splice sites.
-- `description`: Description of the sequence, either in the format `chr{chr}:{position}:{ref_base}:{alt_base}[,optional variant impact]` or `wild-type` for the unmodified sequence.
+- `description`: Description of the sequence, either in the format `chr{chr}:{position} {ref_base}:{alt_base}[,optional variant impact]` or `wild-type` for the unmodified sequence.
 
 Note: The position of the variant is 1-indexed (ClinVar notation) and refers to the position of the variant on the positive strand.