A 45,X male with an X;Y translocation: implications for the mapping of the genes responsible for the mapping of the genes responsible for Turner syndrome and X-linked chondrodysplasia punctata

In a male patient with a 45,X karyotype, the terminal part ofthe Y chromosome short arm was translocated as a single blockon to the X chromosome. This rearranged X chromosome was, inevery regard, the same as that present in XX males resultingfrom an abnormal X-Y interchange. Correlations between the phenotypeof this patient and the extent of the deletions on the X andY chromosomes allowed us to map the genes responsible for mostfeatures of the Turner syndrome between DXS432 and Xqter onthe X chromosome, and the homologous Y genes either on Yp ininterval 4 or on Yq. The molecular analysis of this X-Y translocationallowed us also to reduce the interval for the X-linked recessivechondrodysplasia punctata gene to a 1.5 Mb interval betweenDXS432 and DXS31.