RT Journal A1 TERPLAN KL, COHEN MM T1 CErebellum in partial trisomy 18-reply JF American Journal of Diseases of Children JO American Journal of Diseases of Children YR 1969 FD March 1 VO 117 IS 3 SP 370 OP 371 DO 10.1001/archpedi.1969.02100030372026 UL http://dx.doi.org/10.1001/archpedi.1969.02100030372026 AB To the Editor.—At the time of the publication of our paper,1 structural anomalies in the dentate nuclei of the cerebellum in a patient with cytogenetically proven Down'ssyndrome had not been observed. In a previous paper,2 three clinically diagnosed mongoloids were included among a total of 22 patients with changes in the cerebellum similar to those observed in trisomy D1, together with a variety of anatomical anomalies in various organ systems observed both in trisomy D1 and E. As these cases dated back 15 to 25 years, no cytogenetic data were available. To our knowledge such cerebellar changes have never been reported in a chromosomally proven mongoloid. They do, however, occur quite regularly in the D1 trisomy syndrome.2 Among eight cases of complete trisomy 18 examined by us to date, none exhibited these changes, and it is for this reason that the designation