The Hardy-Weinberg principle states that allele and genotype frequencies in a population remain constant if no evolutionary influences are acting upon it.
Key conditions:
\begin{itemize}
\item Large population size.
\item No mutation, migration, or natural selection.
\item Random mating within the population.
\end{itemize}
Equation:
\[
p^2 + 2pq + q^2 = 1
\]
where:
\begin{itemize}
\item \( p^2 \) = frequency of homozygous dominant genotype,
\item \( 2pq \) = frequency of heterozygous genotype,
\item \( q^2 \) = frequency of homozygous recessive genotype.
\end{itemize}