Background: pre-clinical studies showed that carnosine may have a beneficial cardiovascular effect. We studied the effect of tri-nucleotide repeat (CTGs) polymorphisms in exon 2 of the CNDP1 gene, which codes for carnosinase and is responsible for the degradation of carnosine, on the clinical outcome of Chinese peritoneal dialysis (PD) patients.
Methods: we studied 442 PD subjects. Genotyping was done by direct sequencing of genomic DNA. Patients were followed for 43.5 ± 16.2 months.
Results: the prevalence of 6-6, 5-6, 5-5 and 4-6 CTGs genotypes was 80.3%, 18.6%, 0.9% and 0.2%, respectively. A total of 270 patients (61.1%) developed the primary composite end point during follow-up. The 5-year event-free survival of the 6-6 CTGs and non 6-6 group was 37.1% and 21.3%, respectively (log rank test, p = 0.3).
Conclusion: the CTGs polymorphism of the CNDP1 gene does not affect survival of Chinese PD subjects. The role of carnosine and CNDP1 gene polymorphism in the pathogenesis of cardiovascular disease requires further study.