OBJECTIVETo report on two children manifesting multiple cafe-au-lait spots suspected as neurofibromatosis type 1, and perform NF1 gene mutation analysis.

METHODSBlood samples were collected from the 2 children, their unaffected parents and 100 normal controls. The entire coding region of the NF1 gene was amplified by PCR and subjected to direct sequencing.

RESULTSIn patient 1, a novel frameshift mutation c.1948delT (p.Leu650TyrfsX38) was identified in exon 12 of the NF1 gene. And in patient 2, a previously reported nonsense mutation c.541C>T (p.Gln181X) was revealed in exon 4b. The same mutations were not detected in their unaffected parents or 100 normal controls.

CONCLUSIONThe two patients were diagnosed with neurofibromatosis type 1 by molecular genetic testing. The pathogenic mutations were c.1948delT and c.541C>T, respectively.