Re: Population-Based, Case–Control Study of HER2 Genetic Polymorphism and Breast Cancer Risk

Extract

Altered expression of the protooncogene HER2 (also known as c-erbB-2) gene has been implicated in the carcinogenesis and prognosis of breast cancer and other solid tumors (1,2). It is also a cancer therapeutic target, with antibody-based therapy against the Her2 protein, and a predictive marker for response to breast cancer chemotherapy (3,4).

A single nucleotide polymorphism (SNP) at codon 655, resulting in a guanine to adenine transition (Val655Ile) in the transmembrane domain-coding region of this gene, was identified previously (5). A population-based, case–control study of this polymorphism was reported recently in the Journal (6), and the Val allele was found to be associated with an increased risk of breast cancer, particularly among younger women. However, there is little information on the population distribution of this SNP. This is an important issue in the context of statistically significant ethnic differences in the incidence of breast cancer and of other solid tumors (7).