Abstract
Purpose:
To evaluate the genotypic features of patients with basal laminar drusen (BLD) in association with mesangiocapillary glomerulonephritis (MGN type II) or systemic lupus erythematosus (SLE).
Methods:
Five probands with BLD were studied; of which 4 patients had MGN type II, while 1 patient had SLE. Three forms of genetic analysis were performed. These were DNA sequencing of CFH, analysis of age-related macular degeneration (AMD) associated single nucleotide polymorphisms (SNPs) in CFH, CFB ARMS2 and CFHR1 genes, and high-resolution comparative genomic hybridization (CGH) arrays for the CFH-CFHR1 region for three of the samples.
Results:
A variety of SNPs were identified in CFH. Val62Ile, Gln672Gln, Glu936Asp and Intron 12 (rs6677604) were observed in all patients; while, Asn1050Tyr was noted in two patients (MGN and SLE patient each). Three 402His alleles in a total of 8 chromosomes (37.5% frequency) were observed in the MGN patients. These variants were predicted to provide a range of risk for AMD, ranging from very low (for the SLE patient) to high in the MGN patients. One patient with MGN type II also had a homozygous deletion at the CFHR3-CFHR1 locus.
Conclusions:
BLD is a distinct drusen phenotype seen in young patients with MGN type II or SLE. It is associated with genetic variation within CFH and at the CFH locus. MGN, but not SLE, has a significant risk of progressing to AMD in later life.
Keywords: 504 drusen •
539 genetics •
688 retina