title: A novel p.G112E mutation in BFSP2 associated with autosomal dominant pulverulent cataract with sutural opacities.
abstract: OBJECTIVE
  To identify the genetic defect in a Chinese family with bilateral pulverulent sutural cataract.
  
  
  METHODS
  A three-generation family with congenital cataract was recruited in the study. The study protocol followed the principles of the Declaration of Helsinki. Detailed family history and clinical data were recorded. Genomic DNA was extracted from peripheral blood leukocytes. Candidate gene sequencing was performed to identify the disease-causing mutation. The effects of amino acid changes on the structure and function of proteins were predicted by bioinformatics analysis.
  
  
  RESULTS
  All affected individuals presented pulverulent opacities in the embryonal nucleus and sutures. Direct candidate gene sequencing revealed a heterozygous c. 335 G>A variation in the beaded filament structural protein 2(BFSP2) gene, which resulted in the replacement of a highly conserved glycine by glutamic at codon 112 (p. G112E). Haplotype analysis indicated that the affected members shared a common haplotype with markers near BFSP2. This mutation co-segregated with all affected individuals and was not observed in unaffected members or in 120 ethnically matched controls. Bioinformatic analyses confirmed that the mutation altered the hydrophobic and secondary structure of the protein around the substitution site.
  
  
  CONCLUSIONS
  We report a novel mutation (p.G112E) in the BFSP2 gene, underscoring the physiological importance of the beaded filament protein and supporting its role in human cataract formation.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab , Beijing , China.
authors.forename: Qing
authors.initials: Q
authors.lastname: Liu
authors.forename: Kai Jie
authors.initials: KJ
authors.lastname: Wang
authors.forename: Si Quan
authors.initials: SQ
authors.lastname: Zhu
mesh_terms: D000293:Adolescent; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics; D001483:Base Sequence; D002386:Cataract / Q000235:genetics* / Q000473:pathology; D002648:Child; D002681:China; D004252:DNA Mutational Analysis; D017931:DNA Primers / Q000737:chemistry; D015785:Eye Diseases, Hereditary / Q000235:genetics* / Q000473:pathology; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005799:Genes, Dominant / Q000235:genetics; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D007381:Intermediate Filament Proteins / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D010375:Pedigree; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide
chemical_list: D017931:DNA Primers; D005136:Eye Proteins; D007381:Intermediate Filament Proteins; C084808:phakinin
keywords: BFSP2; congenital cataract; gene; mutation; sutural