Transgenic female mice over-expressing human ornithine decarboxylase ODC gene and their non-transgenic littermates 45 to 49 animals per exposure group were used. In experiments with cells, genotoxic effects increased micronuclei and aneuploidy were reported in two studies at exposure levels higher than those found in the tissues of mobile phone users. These observations were done at low exposure level and a direct effect of temperature elevation can be excluded. The Mobile Classroom is expected to begin shipping from NEC Unified Solutions and certified resellers during Q1 2006. There was no trend in risk of acoustic neuroma in relation to cumulative measures of phone use, and no significant relation between side of phone use and side of tumour.