The majority of the marker chromosomes in Japanese patients with stigmata of Turner syndrome are derived from Y chromosomes.
DNA analyses of 41 individuals with stigmata of Turner syndrome and a 45,X/46,X+mar or 46,X+mar karyotype were carried out. Southern-blot analysis employing 17 Y-specific probes were used to determine whether the marker chromosome was Y-chromosomal in origin. Of the 41 DNA samples from these patients, 23 contained detectable Y-chromosomal DNA. Points of chromosome breakage were distributed over the entire length of the Y long arm. Three individuals, who carry different portions of the Y chromosome, had developed gonadoblastoma. GBY (the gonadoblastoma locus on the Y chromosome) is mapped proximal to DYS132, midway between the 13 Yq loci that we have studied. We also used a polymerase chain reaction technique that could detect 7 loci over the length of the Y chromosome. This technique may be useful for the rapid assessment of marker chromosomes, especially for evaluating the risk of gonadoblastoma.
Nagafuchi
S
S
Department of Congenital Abnormalities Research, National Children's Medical Research Center, Tokyo, Japan.
Tamura
T
T
Nakahori
Y
Y
Takano
K
K
Nishi
Y
Y
Iwatani
N
N
Kitao
M
M
Hori
Y
Y
Konda
S
S
Hasegawa
T
T
D015139:Blotting, Southern; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis; D005260:Female; D005819:Genetic Markers / Q000235:genetics; D006801:Humans; D007564:Japan; D016133:Polymerase Chain Reaction; D012729:Sex Chromosome Aberrations / Q000235:genetics; D014424:Turner Syndrome / Q000235:genetics*; D014998:Y Chromosome / Q000502:physiology*
D005819:Genetic Markers; D004247:DNA