Article

ZFX has a gene structure similar to ZFY, the putative sex determinant and escapes X inactivation

Whitehead Institute for Biomedical Research, Nine Cambridge Center, Massachusetts 02142.
Cell (Impact Factor: 32.24). 07/1989; 57(7):1247-58. DOI: 10.1016/0092-8674(89)90061-5
Source: PubMed

ABSTRACT

The ZFX gene on the human X chromosome is structurally similar to the ZFY gene, which may constitute the sex-determining signal on the human Y chromosome. ZFY and ZFX diverged from a common ancestral gene, as evidenced by similarities in their intron/exon organization and exon DNA sequences. The carboxy-terminal exons of ZFY and ZFX both encode 13 zinc fingers; 383 of 393 amino acid residues are identical, and there are no insertions or deletions. Thus, the ZFY and ZFX proteins may bind to the same nucleic acid sequences. ZFY and ZFX are transcribed in a wide variety of XY and (in the case of ZFX) XX cell lines. Transcription analysis of human-rodent hybrid cell lines containing "inactive" human X chromosomes suggests that ZFX escapes X inactivation. This result contradicts the "dosage/X-inactivation" model, which postulated that sex is determined by the total amount of functionally interchangeable ZFY and ZFX proteins.

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Available from: David Page, Jan 13, 2014
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    • "Zinc finger gene is present in both X-and Y-chromosome (Page et al., 1987; Schneider-Gadicke et al., 1989). Aasen and Medrano (1990) described a quick and efficient method of determining the sex of DNA samples from humans, cattle, sheep, and goats. "
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    ABSTRACT: ABSTRACT Sex determination of domestic animal's meat is of potential value in meat authentication and quality control studies. Methods aiming at determining the sex origin of meat may be based either on the analysis of hormone or on the analysis of nucleic acids. At the present time, sex determination of meat and meat products based on hormone analysis employ gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography-mass spectrometry/ mass spectrometry (HPLC-MS/MS), and enzyme-linked immunosorbent assay (ELISA). Most of the hormone based methods proved to be highly specific and sensitive but were not performed on a regular basis for meat sexing due to the technical limitations or the expensive equipments required. On the other hand, the most common methodology to determine the sex of meat is unquestionably traditional polymerase chain reaction (PCR) that involves gel electrophoresis of DNA amplicons. This review is intended to provide an overview of the DNA based methods for sex determination of meat and meat products.
    Full-text · Article · Oct 2013 · Critical Reviews in Food Science and Nutrition
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    • "Zinc finger gene is present in both X-and Y-chromosome (Page et al., 1987; Schneider-Gadicke et al., 1989). Aasen and Medrano (1990) described a quick and efficient method of determining the sex of DNA samples from humans, cattle, sheep, and goats. "
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    ABSTRACT: Sex determination of domestic animal's meat is of potential value in meat authentication and quality control studies. The job becomes easier if the same assay could serve the purpose for all three species i.e. cattle, sheep and goat. The objective of this study was to develop a simple and accurate PCR-based sex determination protocol, which can be applicable to cattle, sheep and goat meat. Based on the amelogenin gene located on the X and Y chromosomes, a pair of primers was designed and the system of PCR was optimized. Upon PCR amplification, male tissue showed 2 bands, while female tissue resulted in only one band. The accuracy and specificity of the primers was assessed using genomic DNA extracted from meat samples of known sex. The protocol was subjected to a blind test and showed 100% concordance, proving its accuracy and reliability. The technique also claims its utility in resolving legal cases related to sex origin of these animals.
    Full-text · Article · Jun 2013 · Small Ruminant Research
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    • "In metatherian (marsupial) mammals, genes related to ZFX and ZFY are autosomal (3), and it is thought that ZFX and ZFY originated more than 100 million years ago, after the separation of eutherian and metatherian lineages, by translocation of an autosomal segment to the pseudo-autosomal region in a common ancestor of extant eutherians (4). ZFY and ZFX genes code putative transcription activators, characterized by a large N-terminal acidic (activating) domain (approximately 360 amino acids) and a C-terminal DNA-binding domain of 12–13 Cys2-His2 zinc fingers, separated by a short basic nuclear localization signal (5,6). The DNA targets and protein partners of ZFY and ZFX remain to be determined. "
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