TY - JOUR T1 - Correspondence JF - Journal of Medical Genetics JO - J Med Genet SP - 250 LP - 250 DO - 10.1136/jmg.9.2.250 VL - 9 IS - 2 AU - Marcus Pembrey Y1 - 1972/06/01 UR - http://jmg.bmj.com/content/9/2/250.abstract N2 - 300 Multiple ChoicesThis is a pdf-only article and there is no markup to show you.full-text.pdf ER -