Association of an (A-C)n dinucleotide repeat polymorphic marker at the 5 '-region of the aldose reductase gene with retinopathy but not with nephropathy or neuropathy in Japanese patients with Type 2 diabetes mellitus
F. Ichikawa et al., Association of an (A-C)n dinucleotide repeat polymorphic marker at the 5 '-region of the aldose reductase gene with retinopathy but not with nephropathy or neuropathy in Japanese patients with Type 2 diabetes mellitus, DIABET MED, 16(9), 1999, pp. 744-748
Aims Recently an (FL-C)n dinucleotide repeat polymorphic marker in the 5'-r
egion of the ALR2 gene encoding aldose reductase was found to be associated
with diabetic retinopathy in the Chinese population in Hong Kong, and with
nephropathy and neuropathy in the British Caucasian population. The presen
t study assessed the association between the polymorphism and microvascular
complications in Japanese patients with Type 2 diabetes mellitus.
Methods DNA from 87 Japanese patients with Type 2 diabetes mellitus and 90
control subjects with normal glucose tolerance were typed for the polymorph
ic marker by polymerase chain reaction and direct sequencing.
Results Six alleles, namely Z-12, Z-6, Z-4, Z-2, 2, and Z+2 were identified
. There was no significant difference in allele distribution between diabet
ic patients and controls. The Z-2 allele frequency was significantly higher
in subjects with diabetic retinopathy than those without retinopathy (0.35
vs. 0.20, P=0.039), suggesting that aldose reductase is involved in the de
velopment of diabetic retinopathy. In contrast, the microsatellite marker w
as not associated with diabetic nephropathy, peripheral or autonomic neurop
athy. The discrepancy may be partly attributable to the low frequency of Z2 allele in the Japanese subjects.
Conclusions The (A-C)n dinucleotide repeat polymorphism may be a useful gen
etic marker to screen for patients at high risk of retinopathy.