RT Journal Article SR Electronic T1 Y chromosome specific probes identify breakpoint in a 45,X/46,X,del(Y)(pter----q11.1:) karyotype of an infertile male. JF Journal of Medical Genetics JO J Med Genet FD BMJ Publishing Group Ltd SP 330 OP 333 DO 10.1136/jmg.26.5.330 VO 26 IS 5 A1 G C Beverstock A1 J D MacFarlane A1 H Veenema A1 H Hoekman A1 P J Goodfellow YR 1989 UL http://jmg.bmj.com/content/26/5/330.abstract AB An infertile male patient with a 45,X peripheral blood karyotype and a 45,X/46,X,del(Y)(pter----q11.1:) mosaic skin fibroblast karyotype is described. Steroid sulphatase (STS) activity was normal. Recombinant DNA studies using Y chromosome specific probes suggest that almost the entire long arm of the Y chromosome is deleted.