These amino acid frequencies of the top 10% of variants with the
largest \(\mathbb{P}(j=4)\) are compared against natural amino acid
frequencies to test for discrepancies using \(\chi^2\). Table
\ref{amino-acid-distribution} shows the recorded amino acid frequencies with their expected
frequencies taken from \citet{Moura2013}. Interestingly, when taking
the top 3 amino acids with the highest adjusted differences between
observed and expected frequencies for BPD and SCZ, we find that both
disorders are most affected by identical amino acids (Leu, Ser, and
Val), indicating a strong genetic linkage.