Profiling of Germline Mutations in Major Hotspot Codons of TP53 Using PCR-RFLP

Tumor suppressor protein, TP53 also known as the "guardian of the genome" plays a key role in preventing malignant transformation. Almost 50% of human tumors carry mutations in this gene; in the remaining tumors, the TP53 network is functionally inoperative. The majority of TP53 mutations are missense mutations and more than 90% of the missense mutations affect specific codons in the DNA-binding domain, called "hotspot codons." The present study was aimed at analyzing the germline mutation status of four hotspot codons in TP53 namely, codon 175, codon 245, codon 248 (within the DNA binding domain) and codon 72 (outside the DNA binding domain) in cancer cases encountered in a tertiary care hospital in South India by PCR-RFLP. The case-control study included 85-10 subjects respectively. The results of the study indicated that majority of the cancer cases did not harbor germline mutations in the four hot spot codons of TP53. The study further highlights the usefulness of PCR-RFLP as a simple and cost effective tool for checking gene mutations.