#### Founder Principle-Driven Enrichment Calculator

Founder principle-driven enrichment (FPE) is a method that allows isolation of rare BAC recombinants (as rare as 1:10,000 to 1:100,000) without using selectable markers. The web-based calculator presented here enables users to easily determine all possible optimal FPE parameters for any desired cost function, i.e. the specific working conditions.

#### Cost function description

From eq. 21 in the manuscript

$E_\alpha\left(b, r\right) = \dfrac{1}{\log\left(r\right)} \dfrac{M_0}{1 - e^{-\frac{b}{r}}} \left(\alpha b + 1 - \alpha\right)$

Cost function parameter $$\alpha$$ determines the balance between the number of PCR reactions per day vs. lower enrichment rates i.e. more days required to reach target recombinant frequency.