Hi, I just wrote a SeqMaker which can simulate Next Generation Sequencing data with mutations
https://github.com/OpenGene/SeqMaker.jl
The mutation is configured in a JSON config file.
{
    "config":{
        "depth":300,
        "pair-end":true,
        "readlen":151,
        "assembly":"hg19",
        "seq_error_rate":0.001,
        "template_len":{
            "min":140,
            "max":200
        },
        "normal_base_qual":{
            "min":30,
            "max":37
        },
        "seq_error_qual":{
            "min":8,
            "max":20
        }
    },
    "fusion":[
        {
            "name":"ALK-intron19-EML4-intron13",
            "left":"-2:29447873",
            "right":"+2:42526793",
            "rate":0.1
        }
    ],
    "snv":[
        {
            "name":"EGFR-L861Q",
            "chrom":"chr7",
            "pos":55259524,
            "ref":"T",
            "alt":"A",
            "rate":0.2
        },
        {
            "name":"KRAS-G12D",
            "chrom":"chr12",
            "pos":25398284,
            "ref":"G",
            "alt":"A",
            "rate":0.75
        }
    ]
}
                    
                
                 
this is not a common need, usually the read simulators will generate a mutated genome with some characteristics. In your case I am afraid you would need to actually create a custom genome then run a simulator where you turn off the mutation rates.