Supplementary Material for: Mutation Analysis of NPHS1 in a Worldwide Cohort of Congenital Nephrotic Syndrome Patients

<b><i>Background:</i></b> Congenital nephrotic syndrome (CNS) is defined as nephrotic syndrome that manifests within the first 3 months of life. Mutations in the <i>NPHS1</i> gene encoding nephrin, are a major cause for CNS. Currently, more than 173 different mutations of <i>NPHS1</i> have been published as causing CNS, affecting most exons. <b><i>Methods:</i></b> We performed mutation analysis of NPHS1 in a worldwide cohort of 20 families (23 children) with CNS. All 29 exons of the NPHS1 gene were examined using direct sequencing. New mutations were confirmed by demonstrating their absence in 96 healthy control individuals. <b><i>Results:</i></b> We detected disease-causing mutations in 9 of 20 families (45%). Seven of the families showed a homozygous mutation, while two were compound heterozygous. In another 2 families, single heterozygous <i>NPHS1</i> mutations were detected. Out of 10 different mutations discovered, 3 were novel, consisting of 1 splice site mutation and 2 missense mutations. <b><i>Conclusion:</i></b> Our data demonstrate that the spectrum of <i>NPHS1</i> mutations is still expanding, involving new exons, in patients from a diverse ethnic background.