Article

Small deletions of the short arm of the Y chromosome in 46,XY females

Proceedings of the National Academy of Sciences (Impact Factor: 9.81). 11/1986; 83(20):7841-4. DOI: 10.1073/pnas.83.20.7841
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ABSTRACT Structural anomalies of the sex chromosomes provide a means to study the location of genes responsible for sex determination. Recently, a type of sex reversal in humans, the 46,XX male, was shown to result in some cases from translocation of Y chromosome material to the X chromosome. In the present report, another type of sex reversal, the 46,XY female, is shown to result, in two cases, from small deletions of the short arm of the Y chromosome. Prometaphase chromosome analysis showed a 46,X,Yp- karyotype. Several Y chromosome-specific DNA probes were found to be deleted in the two female patients. DNA analysis showed that the two deletions were different but included a common overlapping region likely to be essential for male determination.

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    • "Molecular studies surveying the copy number of Y-specific loci similarly discovered general population duplications and deletions of segments of the chromosome that could be hundreds of kilobases or megabases in size (Jobling et al. 1996; Santos et al. 1998; Saxena et al. 2000; Bosch and Jobling 2003; Fernandes et al. 2004; Repping et al. 2004; Murphy et al. 2007; Balaresque et al. 2008, 2009). Rare pathological CNVs have also been identified , including cytogenetically visible deletions associated with spermatogenetic failure (Tiepolo and Zuffardi 1976) and anomalies of sex determination (Disteche et al. 1986) and three distinct cytogenetically undetectable deletions leading to spermatogenetic failure (Vogt et al. 1996), as well as insertions causing hearing impairment (Wang et al. 2013). In addition, CNVs with milder medically relevant effects have been identified: the gr/gr deletion in the AZFc region of Yq (Repping et al. 2003; Machev et al. 2004) and low TSPY copy number (Giachini et al. 2009), which both slightly increase the risk of spermatogenetic failure, while deletions that remove AMELY have no apparent phenotypic consequences, but confound DNA-based sex tests in forensic analyses (Santos et al. 1998). "
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    • "Generating genetic diversity: recombination mechanisms in AZFc Since the mid 1980s, that polymorphisms in the Yq region later identified as AZFc have been appreciated (Lucotte and Ngo, 1985; Disteche et al., 1986). Yet, a more extensive measure of AZFc genetic diversity in the Y chromosome population was only established in 2006 (Repping et al., 2006). "
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