Molecular Genetics of Achromatopsia in Newfoundland Reveal Genetic Heterogeneity, Founder Effects and the First Cases of Jalili Syndrome in North America. (September 2013)

• Record Type: Journal Article
• Authors: Doucette, Lance; Green, Jane; Black, Coleman; Schwartzentruber, Jeremy; Johnson, Gordon J.; Galutira, Dante; Young, Terry-Lynn
• Is Part Of: Ophthalmic genetics. Volume 34:Number 3(2013:Sep.)
• Page Start: 119
• Page End: 129
• Publication Date: 2013-09
• Subjects: Eye -- Diseases -- Genetic aspects -- Periodicals; Eye Diseases -- genetics -- Periodicals; Eye Diseases -- in infancy & childhood -- Periodicals; 617.7
• DOI: 10.3109/13816810.2013.763993
• Languages: English
• ISSNs: 1381-6810

Abstract

<abstract> <title>Abstract</title> <p>Achromatopsia (ACHM) is a severe retinal disorder characterized by an inability to distinguish colors, impaired visual acuity, photophobia and nystagmus. This rare autosomal recessive disorder of the cone photoreceptors is best known for its increased frequency due to founder effect in the Pingelapese population of the Pacific islands. Sixteen patients from Newfoundland, Canada were sequenced for mutations in the four known achromatopsia genes <italic>CNGA3, CNGB3, GNAT2</italic>, and <italic>PDE6C</italic>. The majority (<italic>n</italic> = 12) of patients were either homozygotes or compound heterozygotes for known achromatopsia alleles, two in <italic>CNGB3</italic> (p.T383fsX and p.T296YfsX9) and three in <italic>CNGA3</italic> (p.R283Q, p.R427C and p.L527R). Haplotype reconstruction showed that recurrent mutations p.T383fsX and p.L527R were due to a founder effect. Aggregate data from exome sequencing, segregation analysis and archived medical records support a rediagnosis of Jalili syndrome in affected siblings (<italic>n</italic> = 4) from Family 0094, which to our knowledge is the first family identified with Jalili Syndrome in North America.</p> </abstract>