??? ??? ?? ? ? ?? ?? ??? ????? ??? ?? ??? ???? ??? ???? ?????. ?? ????? ???? ??? ???? ?? ??? ? ?? ???? ??? ? ????. ?? ????? ??? ????? ??? ???? ?? ???? ??????! A chromosomal abnormality consisting with the absence of one of several copies of chromosome 7 in somatic cells. [from NCI]