RT Journal Article SR Electronic T1 New human double trisomy or tetrasomy. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 75 OP 76 DO 10.1136/jmg.7.1.75 VO 7 IS 1 A1 R K Dhadial YR 1970 UL http://jmg.bmj.com/content/7/1/75.abstract AB