A Rare Compound Heterozygous NAGLU Gene Mutation in Two Siblings with Mucopolysaccharidosis type Iiib

Targeted sequencing confirmed the diagnosis, identifying two heterozygous mutations-an in-frame insertion and a missense mutation-in exon 3 of the <i>NAGLU</i> gene: c.214_237dup (p.Ala72_Gly79dup) and c.625A>C (p.Thr209Pro). This rare genetic finding in two siblings with Sanfilippo syndrome type B underscores the importance of precise mutation identification. Accurate characterization of defective gene variants may provide insights into potential targets for gene therapy in monogenic disorders.