Three of the diseases, MOPD1/TALS, RFMN and LWS are autosomal recessive disorders which have been associated with point mutations in the RNU4atac locus, encoding the U4atac snRNA, an essential snRNA component in the U4atac/U6atac.U5 tri-snRNP. Here, RNU4ATAC is linked to Lowry-Wood syndrome.