Primary open angle glaucoma in a Caucasian population is associated with the p53 codon 72 polymorphism.
OBJECTIVE
Apoptosis has been implicated as the mechanism for retinal ganglion cell death in primary open-angle glaucoma (POAG), a complex neurodegenerative disease. There have been inconsistent reports regarding increased risk of POAG and a polymorphism (Arg72Pro) within the tumor suppressor gene, p53. The goal of this study was to examine the role of this polymorphism in susceptibility to POAG in a Caucasian population from the United States.


METHODS
We generated genotypes in 191 unrelated Caucasian POAG patients and 167 unrelated Caucasian controls for the following polymorphisms within p53: rs1042522 (Arg72Pro), rs17878362 (16 bp Ins/Del), and rs1800371 (Pro47Ser) by PCR amplification followed by restriction digestion and sequence analysis.


RESULTS
There was a significant difference in genotypic frequencies for rs1042522 (Arg72Pro) between POAG patients and controls (chi(2)= 9.56, p=0.008). Individuals who were homozygous for the arginine allele have a 1.9 fold significantly increased risk of developing glaucoma (95%CI: 1.16-2.82, p=0.01). Interestingly, we found that the frequency of the arginine allele was even higher in the normal-tension glaucoma (NTG) subtype compared to high-tension POAG (0.81 versus 0.76).


CONCLUSIONS
Our preliminary results indicate that the arginine variant of rs1042522 within p53 is associated with increased risk of POAG. This variant has increased apoptotic potential, thus the retinal ganglion cells in carriers of the arginine allele may have greater susceptibility to apoptosis.
Department of Ophthalmology, West Virginia University, Morgantown, WV 26506, USA.
Christopher L
CL
Daugherty
Hilda
H
Curtis
Tony
T
Realini
Judie F
JF
Charlton
Sepideh
S
Zareparsi
D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D003062:Codon / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005902:Glaucoma, Open-Angle / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics*; D044465:White People / Q000235:genetics*
D003062:Codon; D016159:Tumor Suppressor Protein p53