Germ-line and acquired mutations of INI1 in atypical teratoid and rhabdoidtumors

We examined 18 atypical teratoid and rhabdoid tumors of the brain and 7 ren al and 4 extrarenal rhabdoid tumors for mutations in the candidate rhabdoid tumor suppressor gene, INI1. Fifteen tumors had homozygous deletions of on e or more exons of the INI1 gene, and the other 14 tumors demonstrated muta tions. Germ-line mutations of INI1 were identified in four children, one wi th an atypical teratoid tumor of the brain and three with renal rhabdoid tu mors. These studies suggest that INI1 is a tumor suppressor gene involved i n rhabdoid tumors of the brain, kidney, and other extrarenal sites.