Two novel mutations in the gene for human α-mannosidase that cause α-mannosidosis

Summary: Mutation analysis performed on two Italian patients with α-mannosidosis allowed the identification of two new mutations, IVS20−2A>G and 322–323insA. The patients were both homozygous for these mutations. The first mutation causes skipping of exon 21, whereas the second causes a frameshift introducing a stop codon at position 160 of the amino acid sequence.