title: A spectrum of novel NPHS1 and NPHS2 gene mutations in pediatric nephrotic syndrome patients from Pakistan.
abstract: BACKGROUND
  Mutations in the NPHS1 and NPHS2 genes are among the main causes of early-onset and familial steroid resistant nephrotic syndrome respectively. This study was carried out to assess the frequencies of mutations in these two genes in a cohort of Pakistani pediatric NS patients.
  
  
  METHODS
  Mutation analysis was carried out by direct sequencing of the NPHS1 and NPHS2 genes in 145 nephrotic syndrome (NS) patients. This cohort included 36 samples of congenital or infantile onset NS cases and 39 samples of familial cases obtained from 30 families.
  
  
  RESULTS
  A total of 7 homozygous (6 novel) mutations were found in the NPHS1 gene and 4 homozygous mutations in the NPHS2 gene. All mutations in the NPHS1 gene were found in the early onset cases. Of these, one patient has a family history of NS. Homozygous p.R229Q mutation in the NPHS2 gene was found in two children with childhood-onset NS.
  
  
  CONCLUSIONS
  Our results show a low prevalence of disease causing mutations in the NPHS1 (22% early onset, 5.5% overall) and NPHS2 (3.3% early onset and 3.4% overall) genes in the Pakistani NS children as compared to the European populations. In contrast to the high frequency of the NPHS2 gene mutations reported for familial SRNS in Europe, no mutation was found in the familial Pakistani cases. To our knowledge, this is the first comprehensive screening of the NPHS1 and NPHS2 gene mutations in sporadic and familial NS cases from South Asia.
authors.affiliation: Centre for Human Genetics and Molecular Medicine, Sindh Institute of Urology and Transplantation, Karachi, Pakistan.
authors.forename: Aiysha
authors.initials: A
authors.lastname: Abid
authors.forename: Shagufta
authors.initials: S
authors.lastname: Khaliq
authors.forename: Saba
authors.initials: S
authors.lastname: Shahid
authors.forename: Ali
authors.initials: A
authors.lastname: Lanewala
authors.forename: Mohammad
authors.initials: M
authors.lastname: Mubarak
authors.forename: Seema
authors.initials: S
authors.lastname: Hashmi
authors.forename: Javed
authors.initials: J
authors.lastname: Kazi
authors.forename: Tahir
authors.initials: T
authors.lastname: Masood
authors.forename: Farkhanda
authors.initials: F
authors.lastname: Hafeez
authors.forename: Syed Ali Anwar
authors.initials: SA
authors.lastname: Naqvi
authors.forename: Syed Adeebul Hasan
authors.initials: SA
authors.lastname: Rizvi
authors.forename: Syed Qasim
authors.initials: SQ
authors.lastname: Mehdi
mesh_terms: D000293:Adolescent; D001208:Asia; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004252:DNA Mutational Analysis / Q000379:methods; D005060:Europe; D005260:Female; D006720:Homozygote; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D009154:Mutation; D009404:Nephrotic Syndrome / Q000235:genetics*; D010154:Pakistan
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D008565:Membrane Proteins; C407223:NPHS2 protein; C113267:nephrin