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We are using Illumina's Somatic Variant Caller (https://www.illumina.com/documents/products/technotes/technote_somatic_variant_caller.pdf) to call somatic variant from tumor sample. Based on the Somatic Variant Caller description, it used Poisson model to calculate p-value for each variant to be true. My question is: Does somatic mutation follow poisson distribution? How? Any comments are appreciated. Thanks

Very precise explanation. Thanks