For example, the reported genetic variants include homozygous LOF alleles in AHI1, C12orf57 and POMGNT1 genes, which are known to underlie the severe neurological disorders, Joubert syndrome39, Temtamy syndrome40 and muscle–eye–brain disease and other muscular dystrophy–dystroglycanopathies,41 respectively. This evidence concerns the gene POMGNT1 and brain disorder.