scholarly journals Sex Chromosome Aneuploidies

10.5772/34426 ◽  
2012 ◽  
Author(s):  
Eliona Demaliaj ◽  
Albana Cerekja ◽  
Juan Piazze
Keyword(s):  
Sex Chromosome ◽  
Sex Chromosome Aneuploidies

Close but not quite: Two cases of sex chromosome aneuploidies outside the scope of cell free DNA screening

2018 ◽  
Vol 38 (8) ◽  
pp. 617-619
Author(s):  
Katelynn G. Sagaser ◽  
Blair Stevens ◽  
Jessica Davis ◽  
Hope Northrup ◽  
Aarti Ramdaney
Keyword(s):  
Sex Chromosome ◽  
Cell Free Dna ◽  
Free Dna ◽  
Sex Chromosome Aneuploidies

Efficiency of Noninvasive Prenatal Testing for Sex Chromosome Aneuploidies

2021 ◽  
pp. 1-9
Author(s):  
Yunfang Shi ◽  
Xiaozhou Li ◽  
Duan Ju ◽  
Yan Li ◽  
Xiuling Zhang ◽  
...  
Keyword(s):  
Screening Tool ◽  
Sex Chromosome ◽  
Diagnostic Testing ◽  
Prenatal Testing ◽  
Maternal Plasma ◽  
Chromosome Abnormalities ◽  
Noninvasive Prenatal Testing ◽  
Sex Chromosome Abnormalities ◽  
Sex Chromosome Aneuploidies ◽  
Mosaic Karyotype

<b><i>Objective:</i></b> This study was designed to investigate the efficiency of noninvasive prenatal testing (NIPT) for screening fetal sex chromosome aneuploidies (SCAs) through sequencing of cell-free DNA in maternal plasma. <b><i>Methods:</i></b> This is a retrospective study on the positive NIPT results for SCAs collected from our hospital between January 2012 and December 2018. Samples with positive NIPT results for SCAs were then confirmed by prenatal or postnatal karyotyping analysis. <b><i>Results:</i></b> After cytogenetic analysis, abnormal karyotypes were confirmed in 104 cases and the overall positive predictive value (PPV) of NIPT for SCAs was 43.40% (102/235). The most frequently detected karyotypes included 47,XXY (<i>n</i> = 42), 47,XXX (<i>n</i> = 20), 47,XYY (<i>n</i> = 16), and 45,X (<i>n</i> = 2). Meanwhile, 10 cases were confirmed with mosaic karyotype 45,X/46,XX and 14 cases with numerical or structural chromosome abnormalities, including a double trisomy 48,XXX,+18. Cytogenetic results from the other 131 cases showed normal XX or XY, which were discordant with NIPT results. Upon analysis of parental karyotypes, 29 (12.34%) showed false positivity in NIPT results that were caused by maternal sex chromosome abnormalities. <b><i>Conclusion:</i></b> NIPT is an effective screening tool for SCA with a PPV of 43.40%. Maternal karyotype abnormalities occurred in 12.34% of the cases with abnormal NIPT. Diagnostic testing of the fetus and the mother are recommended.

Delivering the Diagnosis of Sex Chromosome Aneuploidy: Experiences and Preferences of Parents and Individuals

2018 ◽  
Vol 58 (3) ◽  
pp. 336-342
Author(s):  
Carolina Jaramillo ◽  
Christina Nyquist ◽  
Kirsten A. Riggan ◽  
Jason Egginton ◽  
Sean Phelan ◽  
...  
Keyword(s):  
Medical Care ◽  
Sex Chromosome ◽  
Genetic Diagnosis ◽  
Accurate Information ◽  
Misleading Information ◽  
Telephone Interviews ◽  
Care And Support ◽  
Follow Up Care ◽  
Sex Chromosome Aneuploidies

Increased prenatal diagnoses of sex chromosome aneuploidies (SCAs) amid limited knowledge of their prognoses heighten the need to understand how families contend with the implications of an SCA. To explore the experiences of parents and individuals who received a genetic diagnosis of an SCA (excluding Turner syndrome), we conducted semistructured qualitative telephone interviews with 43 participants affected by these conditions. Parents (n = 35) and individuals (n = 8) expressed almost unanimous interest in more optimistic portrayals of their condition from their providers, even when the prognosis is uncertain. While some participants reported success in receiving accurate information from their provider and identifying supportive resources, numerous families received outdated or misleading information about their condition and lacked direction in accessing follow-up care and support. Parents desire greater coordination of their child’s medical care and access to care that approaches an SCA holistically. Opportunities remain to improve the diagnosis and care of individuals with SCAs.

Sexual Selection, Timing and an X–Y Homologous Gene: Did Homo Sapiens Speciate on the Y Chromosome?

2004 ◽  
Author(s):  
Tim J. Crow
Keyword(s):  
Sexual Selection ◽  
Sex Chromosome ◽  
Homo Sapiens ◽  
Single Gene ◽  
Critical Role ◽  
Hominid Evolution ◽  
Homologous Gene ◽  
Chromosomal Change ◽  
Species Specific ◽  
Sex Chromosome Aneuploidies

This chapter provides a theory of the speciation of modern Homo sapiens, that a single gene played a critical role in the transition from a precursor species. The theory is founded upon the following: firstly, the premise that hemispheric asymmetry is the defining feature of the human brain and the only plausible correlate of language; secondly, an argument for a specific candidate region (the Xq21.3/Yp11.2 region of homology) based upon the reciprocal deficits associated with the sex chromosome aneuploidies, and the course of chromosomal change in hominid evolution; and thirdly, a particular evolutionary mechanism (sexual selection acting on an X-Y-linked gene) to account for species-specific modification of what initially was a saltational change. These postulates relate to the case of modern Homo sapiens. On the basis of the recent literature, the discussion argues that the third premise has general significance as a mechanism of speciation.

scholarly journals Noninvasive prenatal testing for chromosome aneuploidies and subchromosomal microdeletions/microduplications in a cohort of 42,910 single pregnancies with different clinical features

2019 ◽  
Vol 13 (1) ◽  
Author(s):  
Yibo Chen ◽  
Qi Yu ◽  
Xiongying Mao ◽  
Wei Lei ◽  
Miaonan He ◽  
...  
Keyword(s):  
Clinical Features ◽  
Sex Chromosome ◽  
Prenatal Testing ◽  
Maternal Plasma ◽  
Trisomy 13 ◽  
Noninvasive Prenatal Testing ◽  
Detection Rates ◽  
Non Invasive ◽  
Cell Free Fetal Dna ◽  
Sex Chromosome Aneuploidies

Abstract Background Since the discovery of cell-free DNA (cfDNA) in maternal plasma, it has opened up new approaches for non-invasive prenatal testing. With the development of whole-genome sequencing, small subchromosomal deletions and duplications could be found by NIPT. This study is to review the efficacy of NIPT as a screening test for aneuploidies and CNVs in 42,910 single pregnancies. Methods A total of 42,910 single pregnancies with different clinical features were recruited. The cell-free fetal DNA was directly sequenced. Each of the chromosome aneuploidies and the subchromosomal microdeletions/microduplications of PPV were analyzed. Results A total of 534 pregnancies (1.24%) were abnormal results detected by NIPT, and 403 pregnancies had underwent prenatal diagnosis. The positive predictive value (PPV) for trisomy 21(T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosome aneuploidies (SCAs), and other chromosome aneuploidy was 79.23%, 54.84%, 13.79%, 33.04%, and 9.38% respectively. The PPV for CNVs was 28.99%. The PPV for CNVs ≤ 5 Mb is 20.83%, for within 5–10 Mb 50.00%, for > 10 Mb 27.27% respectively. PPVs of NIPT according to pregnancies characteristics are also different. Conclusion Our data have potential significance in demonstrating the usefulness of NIPT profiling not only for common whole chromosome aneuploidies but also for CNVs. However, this newest method is still in its infancy for CNVs. There is still a need for clinical validation studies with accurate detection rates and false positive rates in clinical practice.

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