TP53 haplotype-based analysis and incidence of post-angioplasty restenosis

Haplotype and linkage disequilibrium of TP53-WRAP53 locus in Iranian-Azeri women with breast cancer

Among the cancer susceptibility genes, TP53 is one of the crucial genes involved in cell cycle regulations and, therefore, it greatly affects breast cancer initiation and progression. In addition, WRAP53—a natural antisense transcript—regulates TP53 transcription and, as a protein, modulates the normal cell cycle, which results in breast cancer susceptibility. In this study, we aimed to analyze a haplotype comprising four SNPs, including rs1042522, rs17878362, rs2287499, and rs2287498, which are located at 5′ regions of the TP53 and WRAP53 genes, in 118 patients and 110 healthy controls of the Iranian-Azeri population. In silico studies were conducted using the SIFT, Polyphen2, Fanthmm, RNAsnp, and SNP&GO online servers. Linkage disequilibrium (LD) and D′ for each combination of the markers were calculated via the Haploview program. Our results showed that the GA₁CC haplotype was the most frequent in the studied population. Additionally, no significant LD between any pairwise haplotypes was observed. The GA₁CC and CA₂GC haplotypes were significantly associated with breast cancer susceptibility. Moreover, the in silico analysis revealed the negative effects of rs2287499 and rs1042522 on WRAP53 and P53, respectively. In conclusion, the CA₁GC haplotype was strongly identified as a breast cancer risk factor, and the GA₁CC haplotype was assumed to be a protective factor against breast cancer risk. Hence, these markers may potentially be used as molecular prognostic and predictive biomarkers for breast cancer.

Systematic testing of literature reported genetic variation associated with coronary restenosis: results of the GENDER Study

Background

Coronary restenosis after percutaneous coronary intervention still remains a significant problem, despite all medical advances. Unraveling the mechanisms leading to restenosis development remains challenging. Many studies have identified genetic markers associated with restenosis, but consistent replication of the reported markers is scarce. The aim of the current study was to analyze the joined effect of previously in literature reported candidate genes for restenosis in the GENetic DEterminants of Restenosis (GENDER) databank.

Methodology/Principal Findings

Candidate genes were selected using a MEDLINE search including the terms ‘genetic polymorphism’ and ‘coronary restenosis’. The final set included 36 genes. Subsequently, all single nucleotide polymorphisms (SNPs) in the genomic region of these genes were analyzed in GENDER using set-based analysis in PLINK. The GENDER databank contains genotypic data of 2,571,586 SNPs of 295 cases with restenosis and 571 matched controls. The set, including all 36 literature reported genes, was, indeed, significantly associated with restenosis, p = 0.024 in the GENDER study. Subsequent analyses of the individual genes demonstrated that the observed association of the complete set was determined by 6 of the 36 genes.

Conclusion

Despite overt inconsistencies in literature, with regard to individual candidate gene studies, this is the first study demonstrating that the joint effect of all these genes together, indeed, is associated with restenosis.

Polymorphism of p53 gene codon 72 in Kuwaiti with coronary artery disease and diabetes

BACKGROUND AND AIM

Polymorphism in the p53 gene at codon 72 has been linked to the development of certain diseases including cancer. A possible association between such polymorphism and the development of coronary artery disease (CAD) and diabetes is being investigated, but no conclusive evidence has been reached yet. Our study is the first pilot study to be conducted on Kuwaitis suffering from CAD and diabetes, aiming at investigating the possible existence of the above association.

MATERIALS AND METHODS

We analyzed the genotype distribution and allele frequency of p53 gene at codon 72 in 158 CAD samples and 110 controls, and in 142 diabetic and 130 controls.

RESULTS

Analysis of CAD patients revealed an alarming significant association between the disease and the existence of diabetes (P=0.0007). Also, the CAD patients had significantly higher level of triglyceride (P<0.0001) and cholesterol (P<0.0001) as compared to control. As for the polymorphism in p53 gene codon 72, we could not detect any association with the genotype Pro/Pro, Pro/Arg or Arg/Arg distribution (P=0.28) or allele (Pro or Arg) frequency (P=0.25) in the CAD patients. Similarly, no association was found with the genotype Pro/Pro, Pro/Arg or Arg/Arg distribution (P=0.44) or allele (Pro or Arg) frequency (P=0.26) in the diabetic patients.

CONCLUSION

CAD seems to be strongly linked to diabetes in Kuwait. Polymorphism in the p53 gene at codon 72 revealed no significant association with the development of CAD or diabetes in Kuwait, which confirms other similar results obtained in the US and Asia.