(A) Pedigree of the affected family and partial electropherograms of exon 9 of the NIPBL gene. White symbols indicate unaffected individuals, whereas black symbol indicate the affected individual. The sequencing analysis performed on genomic DNA from the patient peripheral blood lymphocytes (v) and oral mucosa epithelial cells (vi) shows similar heights of the peaks of the allele carrying the c.1445_1448delGAGA mutation in both tissues. Wild-type electropherograms identified in the normal parents are also indicated (i-iv). (B) Schematic model of the NIPBL gene. Sequence features of human NIPBL protein previously reported are indicated [23, 30] . The open reading frame of NIPBL gene is marked in light grey. The exon 9 of the NIPBL gene is highlighted in red.