C(-106)T polymorphism of the aldose reductase gene and the progression rate of diabetic retinopathy.
OBJECTIVE
To study the C(-106)T polymorphism in the promoter of the aldose reductase (ALR2) gene: (a) its local prevalence and (b) its modulation of the susceptibility for developing retinopathy.


METHODS
DNAs of 96 control subjects and 53 long-standing (duration 17.9+/-5.4 years) type-2 diabetic patients were analyzed by PCR-RFLP with BfaI enzyme. Retinopathy was graded with 2-eye, 7-field fundus color photography. The IMF-HbA1c was the arithmetic mean of all HbA1c's of each patient.


RESULTS
The genotypes in the controls were CC=57 (59.4%), CT=32 (33.3%) and TT=7 (7.3%), with Hardy-Weinberg chi(2)=0.793 (p>0.50). Among 53 diabetics, CC=24 (45.3%), CT=26 (49.0%) and TT=3 (5.7%). The correlation between IMF-HbA1c and retinopathy progression rate was significant on CC (r=0.6102, p=0.0072) but not in CT+TT genotypes (r=0.26, p=0.1811).


CONCLUSIONS
In Chilean adults, the frequency of the C(-106)T polymorphism of the ALR2 gene was similar to that reported by others. Type-2 diabetics with the CC genotype were more susceptible for developing retinopathy as a result of chronic hyperglycemia than those with the CT or TT genotype.
Olmos
Pablo
P
Department of Nutrition and Diabetes, College of Medicine, Pontificia Universidad Católica de Chile, Alameda 340, Santiago 6513492, Santiago, Chile. polmos@med.puc.cl <polmos@med.puc.cl>
Bastías
María-Juliana
MJ
Vollrath
Valeska
V
Toro
Luis
L
Trincado
Arturo
A
Salinas
Pablo
P
Claro
Juan-Carlos
JC
López
José-Manuel
JM
Acosta
Ana-María
AM
Miquel
Juan-Francisco
JF
Castro
Juan
J
D000449:Aldehyde Reductase / Q000235:genetics*; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D003930:Diabetic Retinopathy / Q000145:classification / Q000201:enzymology / Q000235:genetics* / Q000503:physiopathology; D018450:Disease Progression; D005838:Genotype; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D008137:Longitudinal Studies; D020641:Polymorphism, Single Nucleotide; D012016:Reference Values; D012189:Retrospective Studies
D000449:Aldehyde Reductase; D004247:DNA; D006442:Glycated Hemoglobin