Hi Andrea,
It looks the MutationMapper tool wants the data in tab (or space delimited format). Also, for lollipop rendering, the columns should start with Chromosome, Start_Position, End_Position, Reference_Allele, and Variant_Allele.
Best,
-Benjamin
| Chromosome | Start_Position | End_Position | Reference_Allele | Variant_Allele |
| 17 | 7673821 | 7673821 | C | G |
| 17 | 7673821 | 7673821 | C | T |
| 17 | 7675189 | 7675189 | C | G |
| 17 | 7674246 | 7674246 | C | A |
| 17 | 7675113 | 7675113 | C | T |
| 17 | 7675119 | 7675119 | C | T |
| 17 | 7670649 | 7670649 | C | T |
| 17 | 7676215 | 7676215 | C | T |
| 17 | 7674945 | 7674945 | C | T |
| 17 | 7674951 | 7674951 | C | T |
| 17 | 7674954 | 7674954 | C | T |