Ring Y chromosome: cytogenetic and molecular characterization.
A female patient with Turner syndrome and the karyotype mos45,X/46,X,r(Y)/46,XY is described. Physical mapping of the ring chromosome by Y-specific single-copy and moderately repeated DNA sequences as molecular probes showed that, in addition to the heterochromatic part of Yq, a considerable portion of the Yp has also been lost in the course of the rearrangement. Thus, molecular findings provide independent support that this structurally abnormal sex chromosome is a ring Y and agree with the generally accepted model of ring formation requiring breaks in both chromosome arms. Clinical consequences of Y chromosome mosaicism in patients with Turner syndrome are discussed.
Wegner
R D
RD
Institut für Humangenetik, Freie Universität, Berlin, Germany.
Scherer
G
G
Pohlschmidt
M
M
L'Allemand
D
D
Gal
A
A
D015139:Blotting, Southern; D002648:Child; D002871:Chromosome Banding; D004247:DNA / Q000032:analysis; D005260:Female; D015321:Gene Rearrangement; D005819:Genetic Markers; D006801:Humans; D009030:Mosaicism; D012303:Ring Chromosomes; D014424:Turner Syndrome / Q000235:genetics*; D014998:Y Chromosome / Q000648:ultrastructure*
D005819:Genetic Markers; D004247:DNA