Somatic variant caller

Question

[CY]

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

Answer 1

[markus.riester]

The variant caller assumes sequencing errors are Poisson distributed. Looks like you get a call when the alt allele has a less than 1% chance of being a sequencing error given the number of supporting reads and the predefined error rate.

[CY]

Very precise explanation. Thanks