TP53 codon 72 polymorphism in pigmentary phenotypes

Abstract

The p53 protein exerts different cellular functions, and recent findings have demonstrated its influence on the cascade of skin pigmentation during UV exposure. Among TP53 gene polymorphisms, the most studied is the G to C transversion in exon 4 at codon 72, which results in three distinct genotypes, Arg/Arg, Pro/Pro and Arg/Pro, each one encoding different p53 isoforms. Therefore, this study aimed to determine the relationship between TP53 codon 72 polymorphism and skin protection against sunburn. Genomic DNA was extracted from peripheral blood samples and genotyping was performed by PCR and confirmed by restriction enzyme digestion. The genotype frequency was 50% for Arg/Arg and 14.6% for Pro/Pro genotype. The frequency of heterozygous subjects was 35.4%. In our population, p53 genotypes were in Hardy-Weinberg (HW) equilibrium (X2 HM less than 3.84), showing a predominance of arginine allele (total Arg allele frequency of 68%). No significant association between p53 genotype and skin colour, hair or eye colour and susceptibility to sun exposure was found. However, further analysis demonstrated a significant association between the genotype Pro/Pro and blue/green eyes among participants who presented redness (P=0.016). Our findings indicate susceptibility to sun exposure when this phenotype (eye colour) occurs simultaneously with Pro/Pro genotype.

Assessment of changes in the brca2 and p53 genes in breast invasive ductal carcinoma in northeast Brazil

“…These findings are not in line with a recent study of TP53 polymorphism among 96 individuals [36] from a Brazilian population where was found a high prevalence of Arginine allele (68%) showing a contrast to our study where Arginine allele frequency was 38% (19 of 50). However, we did not find an association between p53 genotype and breast cancer development.…”

Role of CXCL12, TP53 and CYP1A1 gene polymorphisms in susceptibility to pediatric acute lymphoblastic leukemia

“…The aforementioned polymorphism, which is the most widely studied polymorphism of TP53, refers to a G to C transversion in exon 4 at codon 72 and results in the three following genotypes: Arginine/Arginine (Arg/Arg), Arginine/Proline (Arg/Pro) and Proline/Proline (Pro/Pro). It has been shown that the Arg allele (major allele) predominates over the Pro allele (13). TP53 is a tumor suppressor protein that is responsible for the maintenance of genome stability and is considered to weaken the migration of cancer cells (14).…”