In ADA-SCID, babies lack the ADA enzyme needed to make immune cells, causing a severe combined immunodeficiency disorder that requires isolation in sterile environments.

• ADA-SCID的婴儿缺少繁殖免疫细胞时所需的ADA酵素而造成SCID，这种病人需要被隔离在一个无菌的环境中。