Range 
normal lymphocytes 7.67×10^−9±1.3×10^−9: colorectal epithelial cells 3.97×10^−8±2×10^−9 mutation/base/year

Organism 
Human Homo sapiens 
Reference 
Tomasetti C, Vogelstein B, Parmigiani G. Half or more of the somatic mutations in cancers of selfrenewing tissues originate prior to tumor initiation. Proc Natl Acad Sci U S A. 2013 Feb 5 110(6):19992004. doi: 10.1073/pnas.1221068110. p.2001 left column top paragraphPubMed ID23345422

Method 
"The expected value for the number XS(t) of passenger mutations
that originated in the precancer phase during tissue selfrenewal
(Materials and Methods) is estimated to be
E[XS(t)]=S×u×t [1]
where E is the expectation operator, S is the total number of
DNA bases sequenced, u is the probability of a point mutation
per base per cell division, and t is the number of times the tissue has selfrenewed before tumor initiation." 
Comments 
"Using this formula [see Method section above], the
slopes derived from the data regressions, and letting S=3×10^7
(wholeexome sequencing), the number of somatic mutations
accumulated per base per year are estimated to be 7.67×10^9±1.3×10^9 (SE) in the normal lymphocytes that were precursors
to CLL [chronic lymphocytic leukemia], and 3.97×10^8±2×10^9 (SE) in colorectal epithelial
cells." 
Entered by 
Uri M 
ID 
111248 