FAS and Menkes disease: We performed protein modelling and receptor-ligand docking, as well as differential transcript usage (DTU) and splicing prediction.<h4>Results</h4>We identified ultrarare heterozygous variants in <i>TLR9</i> (chr3:52222299 G>C and chr3:52223761 C>A), <i>TNFRSF1B</i> (chr1:12167150 C>T and chr1:12202100 G>A), and FAS (chr10:89003139 G>A and chr10:89008919 C>T) in MD patients.