[Loss of heterozygosis on the short arm of chromosome 3. Question of the encoding gene for thyroid hormone receptor].

Prognosis of breast tumor patients is not clearly-defined. New marker should be useful. A new field of investigation concerns genetic abnormalities in breast tumors. Oncongene amplification and loss of heterozygosity are the most common alterations. 30% of breast tumors show a loss of heterozygosity on chromosome 3p, where thyroïd hormone receptor, c-erbA-beta is localised. We suggest a potential role for this genetic alteration in breast tumorigenesis.