RT Journal Article SR Electronic T1 A further example of human blood group chimaerism. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 279 OP 281 DO 10.1136/jmg.14.4.279 VO 14 IS 4 A1 I O Szymanski A1 C A Tilley A1 M C Crookston A1 T J Greenwalt A1 S Moore YR 1977 UL http://jmg.bmj.com/content/14/4/279.abstract AB Blood group chimaerism was detected in a healthy fertile woman, not known to be a twin. Her peripheral lymphocytes had a male karyotype (46/XY); fibroblasts cultured from her skin had a female karyotype (46/XX). The mechanism of chimaerism could not be established.