The majority of the marker chromosomes in Japanese patients with stigmata of turner syndrome are derived from Y chromosomes

Abstract

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.

Frequency of Y chromosomal material in Mexican patients with Ullrich-Turner syndrome

“…The frequency of Y-derived marker chromosomes also differs considerably: our frequency was 25%, Held et al [1992] reported 87%, Nagafuchi et al [1992] 56%, Coto et al [1995] 100%, andPatsalis et al [1997] 92%. These variations are probably due to the different number of patients with marker chromosomes included in each sample.…”

Sex chromosome markers: Characterization using fluorescence in situ hybridization and review of the literature

“…All seven patients with a Y-derived marker were phenotypic females but demonstrated a reported milder Ullrich-Turner syndrome phenotype (specifically with respect to somatic anomalies) than their counterparts with X-chromosome derived markers. The frequency of Y-derived marker chromosomes in patients with Ullrich-Turner syndrome found in this study and literature review (14%) is much lower than that recently reported by Nagafuchi et al [1992].…”

Identification of Y chromatin directly in gonadal tissue by fluorescence in situ hybridization (FISH): Significance for Ullrich-Turner syndrome screening in the cytogenetics laboratory

“…Y material has been detected in the blood of UTS individuals by PCR-based strategies or Southern blot analysis. However, these studies did not examine the gonads or other tissues to assess the distribution of the Y chromatin [Ostrer and Clayton, 1989;Medlej et al, 1992;Nagafuchi et al, 1992;Binder et al, 1995;Coto et al, 1995;Kocova et al, 1995]. It is important to gather information regarding the correlation between detected Y chromatin in lymphocytes vs. the distribution in the gonads, since it is believed to be the presence of Y chromatin in the gonads that confers the risk for gonadoblastoma.…”