TY - JOUR T1 - Correction JF - Journal of Medical Genetics JO - J Med Genet SP - 159 LP - 159 DO - 10.1136/jmg.18.2.159 VL - 18 IS - 2 A2 - , Y1 - 1981/04/01 UR - http://jmg.bmj.com/content/18/2/159.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -