ESPE Abstracts

Introduction: Microalbuminuria is the earliest sign of diabetic nephropathy. Cubilin encoded by the CUBN gene is one of the receptor proteins accountable for albumin reabsorption in proximal renal tubules. Cubulin gene (CUBN) was identified as a significant locus for albuminuria. A strong association between CUBN variant rs1801239 and albuminuria was detected in general population.

Aim of the work: The aim of the current work was to determine possible association between CUBN gene variants rs1801239 and rs1801222 and the development of microalbuminuria in patients with type1 diabetes mellitus.

Subject and Methods: Assay of cubulin gene variants rs1801239 and rs1801222 was performed using real time PCR in 3 groups of patients (40 patients with type 1 diabetes and microalbuminuria, 40 patients with type 1 diabetes without microalbuminuria and 40 healthy controls). Clinical and laboratory characteristics of the patients were studied.

Results: The mean age of patients in microalbuminuria group was 13.23±3.54 years, however those in normoalbuminuric group was 12.99 ±3.27 years with no significant difference between both groups (P = 0.52). All patients with diabetes were on multiple daily injection basal/ bolus insulin regimen. The mean insulin dose was (1.21 ± 0.29 U/Kg/day) among microalbuminuria group and (1.14 ± 0.30U/Kg/day) among the normoalbuminuric group, with no statistically significant difference between both groups (P = 0.304). Three genotypes of CUBN variant rs1801239; TT, TC and CC were recognized, with no significant difference between cases and controls (p value = 0.496). Additionally, no statistically significant difference was reported between normoalbuminuric and microalbuminuria groups regarding CUBN variants rs1801239 (p value = 0.413). Three genotypes of CUBN variant rs1801222; GG, GA and AA were recognized, with no significant difference either between cases and controls (p value = 1.000) or between normoalbuminuric and microalbuminuria groups (p value = 0.186). HbA1C at the time of study was significantly correlated with albumin/creatinine ratio (p value = 0.017).

Conclusion: There is no association between Cubulin gene (CUBN) variants rs1801239 and rs1801222 and microalbuminuria in the studied patients with type 1 diabetes.