????? ??? ??, ?? ??? ??? ??? ? ?? ?? ??????. ???? ???? ??? ? ?? ?? ??? ?????.????? ??? ????? ???? ????.????? ???? ??? ??? ??? ???? ?????.A chromosomal abnormality consisting of your absence of one of several copies of chromosome seven in somatic cells. [from NCI]Retinoblastoma is usually a malignant tumor with the producing retina that occurs in y