In contrast, Lugol staining methods were not used in most studies regarding p53 mutational status in oesophageal precancerous lesions such as dysplasia, BCH, and esophagitis (Yang and Qiu, 1987; Qiu and Yang, 1988; Wang et al, 1990; Bennett et al, 1992; Wang et al, 1993; Gao et al, 1994; Greenblatt et al, 1994; Jaskiewicz and De Groot, 1994; Parenti et al, 1995; Shi et al, 1999; Mandard et al, 2000). This evidence concerns the gene TP53 and choreatic disease.