Genotype at the aldose reductase locus affects retinopathy-free survival in type I diabetes

Abstract EN

The aim of this study is to examine whether the retinopathy-free survival in diabetics is linked to the genotype at the Adose Reductase Locus.

Two hundred and fifty-six Australian adolescents with type 1 diabetes were attending for complication, screenings were genotyped.

One microsatellite at the aldose reductase was amplified by Polymerase chain reaction to produce fragments of 126-152 base pair (Z = 138).

Kaplan-Meier survival analysis was used to determine the duration free of retinopathy according to genotypes Z - 2 / Z - 2, Z - 2 / non Z - 2 and non Z - 2 / non Z - 2.

A stereoscopic fundal photography was performed; blinded to the patients' genotype.

The presence of a background retinopathy was defined as any microaneurysm or hemorrhage.

The results of our study show that, Median survival free of retinopathy was significantly shorter in patients having the Z-2 allele (p = 0.014).

When survival analysis was performed on combinations of both Z-2 and Z + 2, the only significant difference was between Z +2 / non Z +2 and non Z + 2 / non Z + 2 (p = 0.04).

We concluded that survival free of retinopathy was significantly reduced in Australian patients with a Z-2 allele with less evidence for other alleles.

This may represent that some sort of protective mechanism of retinopathy in patients with absent Z-2 allele.