Neutral fixation and substitution rate
In the ideal neutral diploid population, a new single-copy allele has eventual fixation probability 1/(2N).
Key knowledge
In the ideal neutral diploid population, a new single-copy allele has eventual fixation probability 1/(2N). Multiplying this probability by the expected 2Nμ new mutations per site per generation gives a neutral substitution rate μ. This distinguishes substitutions that become fixed from the number of new mutations, and does not assert that all real molecular changes are neutral.
Values and equations
Pfix = 1/(2N); kneutral = (2Nμ)Pfix = μ
- Pfix
- eventual fixation probability of one new neutral copy 1
- N
- number of diploid reproducing individuals in the ideal model individual count
- μ
- mutation rate per site per generation for the specified class site⁻¹ generation⁻¹
- kneutral
- expected substitution rate in that class site⁻¹ generation⁻¹
Conditions and scope
- The calculation assumes an appropriate neutral constant-size randomly reproducing model; selection and demographic/model complications need separate treatment.
- μ is the mutation rate for the specified neutral class and time unit; neutrality is a hypothesis assessed with additional evidence.
Sources · 1
References
Sources retain their recorded scope. A source link alone does not establish verification of every statement.
Evidence and review
Read single-copy fixation, new-mutation input and substitution-rate product; excluded assertion that only neutral variants can contribute substitutions and dated numerical fractions.
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Entry details
Permanent link to this entry ↗- Record identity
- uni-bio-neutral-substitution
- Revision
- core.1
- Structured reference record
- University core expansion