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Zanetti Simone - - 2013
How is sex determined? In the animal kingdom, there are diverse sets of mechanisms for determining organismal sex, with the predominant ones being chromosomally based, either a dominant-acting sex chromosome or the ratio of the number of X chromosome to autosomes, which lead to oocyte-producing females and sperm-producing males. The ...
Erhart Daniel - - 2012
We established a data set of 17 Y-STRs of 261 males from the Tyrolean district of Reutte. In total we observed 228 different haplotypes, 203 of which were unique and 25 occurred between two and four times. The haplotype diversity was 0.9987 and the discrimination capacity was 0.8736. Further, samples ...
Battaglia Francesco - - 2012
Patients with 46,XY complete gonadal dysgenesis (Swyer syndrome) are characterized by the presence of female internal genital tract and bilateral streak gonads in a phenotypic female. These women have a high risk of developing rare type II malignant germ cell tumors. We report a rare case of a 33-year-old 46,XY ...
Lentini E - - 2012
While there has been increasing support for the existence of cerebral sex differences, the mechanisms underlying these differences are unclear. Based on animal data, it has long been believed that sexual differentiation of the brain is primarily linked to organizational effects of fetal testosterone. This view is, however, in question ...
Thorvaldsen Joanne L - - 2012
During the development of female mammals, one of the two X chromosomes is inactivated, serving as a dosage-compensation mechanism to equalize the expression of X-linked genes in females and males. While the choice of which X chromosome to inactivate is normally random, X chromosome inactivation can be skewed in F1 ...
Wang Jianping - - 2012
Sex determination in papaya is controlled by a recently evolved XY chromosome pair, with two slightly different Y chromosomes controlling the development of males (Y) and hermaphrodites (Y(h)). To study the events of early sex chromosome evolution, we sequenced the hermaphrodite-specific region of the Y(h) chromosome (HSY) and its X ...
Divar Mohammad Reza - - 2012
In the current study we aimed to use PCR to investigate the presence of fetal DNA in the bovine (Bos taurus) cervical secretions and maternal serum, and to assess the effectiveness of this method in fetal gender determination. Pregnant uteri and pre-slaughter maternal blood samples were collected from 21 Holstein ...
Weingartner Laura A - - 2012
The sex chromosomes of the tropical crop papaya (Carica papaya) are evolutionarily young and consequently allow for the examination of evolutionary mechanisms that drive early sex chromosome divergence. We conducted a molecular population genetic analysis of four X/Y gene pairs from a collection of 45 wild papaya accessions. These population ...
Eisenberg Michael L - - 2012
In recent years, investigators have noted a trend toward a declining proportion of male births in many industrialized nations. While men bear the sex-determining chromosome, the role of the female partner as it pertains to fertilization or miscarriage may also alter the gender ratio. We attempted to determine a man's ...
Giummo Jesse - - 2012
X-linked genetic differences between male and females have been posited to cause greater variance in cognitive ability in males. Males with only one X chromosome tend to express the genes on the X chromosome more fully than females, who express an "average" of their two X chromosomes due to X-inactivation. ...
Handyside Alan H - - 2012
Chromosome aneuploidy is a major cause of pregnancy loss, abnormal pregnancy and live births following both natural conception and in vitro fertilisation (IVF) and increases exponentially with maternal age in the decade preceding the menopause. Molecular genetic analysis has shown that these are predominantly maternal in origin and trisomies most ...
Ntali Georgia - - 2012
Background: Turner syndrome is hypothesized to result from haploinsufficiency of certain genes expressed from both sex chromosomes that escape X inactivation. Case Report: We present the rare case of a 4-year-old boy who was referred to the pediatric endocrinology unit for evaluation of slight growth delay. Results: Standard cytogenetic analysis ...
Drosopoulou Elena - - 2012
The olive fruit fly, Bactrocera oleae, has a diploid set of 2n = 12 chromosomes including a pair of sex chromosomes, XX in females and XY in males, but polytene nuclei show only five polytene chromosomes, obviously formed by five autosome pairs. Here we examined the fate of the sex chromosomes in ...
Pala Irene - - 2012
Newer parts of sex chromosomes, neo-sex chromosomes, offer unique possibilities for studying gene degeneration and sequence evolution in response to loss of recombination and population size decrease. We have recently described a neo-sex chromosome system in Sylvioidea passerines that has resulted from a fusion between the first half (10 Mb) ...
Hirai Hirohisa - - 2012
Chromosomes of schistosome parasites among digenetic flukes have a unique evolution because they exhibit the sex chromosomes ZW, which are not found in the other groups of flukes that are hermaphrodites. We conducted molecular cytogenetic analyses for investigating the sex chromosome evolution using chromosome paint analysis and BAC clones mapping. ...
Onesimo Roberta - - 2012
Deletions of the short arm of chromosome 9 are associated with two distinct clinical entities. Small telomeric 9p24.3 deletions cause genital anomalies in male subjects, ranging from disorder of gonadal sex to genital differentiation anomalies, while large terminal or interstitial deletions result in 9p-malformation syndrome phenotype. The critical region for ...
Zhou Qi Q Department of Integrative Biology, University of California Berkeley, Berkeley, CA 94720, - - 2012
Most species' sex chromosomes are derived from ancient autosomes and show few signatures of their origins. We studied the sex chromosomes of Drosophila miranda, where a neo-Y chromosome originated only approximately 1 million years ago. Whole-genome and transcriptome analysis reveals massive degeneration of the neo-Y, that male-beneficial genes on the ...
Goñi Beatriz - - 2012
Spontaneous crossing over in males of Drosophila ananassae has been well demonstrated using F(1) individuals from crosses between marker stocks and wild type strains. However, the question of its occurrence in males from natural populations remained open. Here we present the cytological evidence that crossing over does occur in males ...
Sťáhlavský F - - 2012
The karyotypes of pseudoscorpions of the family Atemnidae (Arachnida: Pseudoscorpiones) were studied for the first time. Karyotype data for 7 species have been obtained. The diploid chromosome numbers of most species considerably exceed the numbers reported in pseudoscorpions so far, with males ranging between 65 and 143. In spite of ...
Shamsi M B - - 2012
Male infertility is a multi-factorial disorder, and identification of its etiology in an individual is critical for treatment. Systematically elucidating the underlying genetic causes (chromosomal and Yq microdeletion) and factors, such as reactive oxygen species (ROS) levels and total antioxidant capacity (TAC), which both contribute to sperm DNA damage, may ...
Deakin J E - - 2012
Marsupial and monotreme mammals fill an important gap in vertebrate phylogeny between reptile-mammal divergence 310 million years ago (mya) and the eutherian (placental) mammal radiation 105 mya. They possess many unique features including their distinctive chromosomes, which in marsupials are typically very large and well conserved between species. In contrast, ...
Juriloff Diana M - - 2012
Females have long been known to be in excess among cranial neural tube defect (NTD) cases. Up to two thirds of human anencephalics and mouse exencephalics from various genetic causes are female, but the cause of this female excess is unknown. It appears not to be attributable to gonadal hormones, ...
Song Seung-Hun - - 2012
Male factor infertility is present in up to 50% of infertile couples, making it increasingly important in their treatment. Although most research into the genetics of male infertility has focused on the Y chromosome, male factor infertility may result from other genetic factors. We utilized the whole genome array comparative ...
Seal Alan G - - 2012
Sex can sometimes lead to complications. In some crops, 2n gametes have been exploited by plant breeders to transfer genetic variation between taxa of different ploidy levels. However, their role and use in dioecious genera have received relatively little attention. In the dioecious genus Actinidia (kiwifruit), seedling populations usually segregate ...
Kuan L-C - - 2012
Structural rearrangement in the Y chromosome is closely involved in spermatogenesis. However, several Y chromosome variants may have no deleterious effects on male reproduction. Here, we report two cases of Y chromosomal duplication from incidental findings. Their FISH analysis revealed direct duplication of large segments of short and long arms ...
Martinez V - - 2012
Relatively large rates of response to traits of economic importance have been observed in different selection experiments in salmon. Several QTL have been mapped in the salmon genome, explaining unprecedented levels of phenotypic variation. Owing to the relatively large selection intensity, individual loci may be indirectly selected, leaving molecular footprints ...
Ma Yan - - 2012
Short tandem repeat (STR) multiplexes with the amelogenin (AMEL) gene as a gender marker have been used as a routine tool of forensic DNA analysis. It has been reported that AMEL-based gender detection could misidentify a known male as a female due to the dropout of amelogenin Y (AMELY) allele. ...
Yannic Glenn - - 2012
We investigated sex specificities in the evolutionary processes shaping Y chromosome, autosomes, and mitochondrial DNA patterns of genetic structure in the Valais shrew (Sorex antinorii), a mountain dwelling species with a hierarchical distribution. Both hierarchical analyses of variance and isolation-by-distance analyses revealed patterns of population structure that were not consistent ...
Isrie M - - 2012
Genome-wide array comparative genome hybridization has become the first in line diagnostic tool in the clinical work-up of patients presenting with intellectual disability. As a result, chromosome X-copy number variations are frequently being detected in routine diagnostics. We retrospectively reviewed genome wide array-CGH data in order to determine the frequency ...
Küpper Clemens - - 2012
Two models, Z Dosage and Dominant W, have been proposed to explain sex determination in birds, in which males are characterized by the presence of two Z chromosomes, and females are hemizygous with a Z and a W chromosome. According to the Z Dosage model, high dosage of a Z-linked ...
Sato Fumio - - 2012
A Thoroughbred colt with ambiguous external genitalia was presented for clinical and histological examinations. The colt had a short penis, located between his hind limbs and faced backward. The measurements of luteinizing hormone, follicle stimulating hormone, testosterone and ir-inhibin showed a tendency to increase gradually from April. Both sex-determining region ...
Jiménez R - - 2012
Gonads are the only organs with 2 possible developmental pathways, testis or ovary. A consequence of this unique feature is that mutations in genes controlling gonad development give rise not only to gonadal malformation or dysfunction but also to frequent cases of sex reversal, including XY females, XX males and ...
Stouffs Katrien - - 2012
The X and Y chromosomes, the sex chromosomes, are important key players in germ cell development. Both chromosomes contain genes that are uniquely expressed in male spermatogenesis. Furthermore, these chromosomes are special because men only have a single copy of them. These features make the sex chromosomes interesting for studying ...
Campbell Polly P Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, Arizona 85721, USA. - - 2012
Hybrid sterility in the heterogametic sex is a common feature of speciation in animals. In house mice, the contribution of the Mus musculus musculus X chromosome to hybrid male sterility is large. It is not known, however, whether F1 male sterility is caused by X-Y or X-autosome incompatibilities or a ...
Forman Eric J - - 2012
Interest in using aneuploidy screening to select embryos has been renewed with the introduction of new methods for comprehensive chromosome screening (CCS) that evaluate all 24 chromosomes. With a series of experiments providing level I evidence of accuracy, reliability, safety, predictive value, and clinical efficacy, CCS-based selection of a single ...
Li Dingyang - - 2012
To detect incidences and the types of chromosomal abnormalities in Chinese men with infertility and determine chromosomal factors association with various phenotypes. Semen analysis and karyotype analysis by G-banding were carried out in 4,659 idiopathic infertile males; additionally, multiplex PCR using nine specific sequence-tagged sites (STSs) was used to detect ...
de Volo Chiara Palka Bayard - - 2012
We report the clinical and molecular investigations in a girl with 46,X,-X,+der(X)t(X;Y)(p22;q11) de novo karyotype who presented an intricate phenotype characterized by mental retardation and facial dysmorphisms in combination with short stature. The structure of the derivative X chromosome was studied using BAC array-CGH which disclosed the Xp22 breakpoint between ...
Pereira Vânia - - 2012
Due to differences in transmission between X-chromosomal and autosomal DNA, the comparison of data derived from both markers allows deeper insight into the forces that shape the patterns of genetic diversity in populations. In this study, we applied this comparative approach to a sample of Portuguese Roma (Gypsies) by analyzing ...
Dai R-L - - 2012
We investigated the frequency and types of Y-chromosome microdeletions and chromosomal anomalies in non-obstructive azoospermic and severely oligozoospermic infertile males in northeastern China. The sample consisted of 519 infertile males (456 azoospermic, 63 severely oligozoospermic). PCR assays for Y-chromosome microdeletions and chromosome analysis were performed on all patients and controls. ...
Park Myung Jin - - 2012
We performed a molecular characterization of Korean Y-chromosomal haplogroups using a combination of Y-chromosomal single nucleotide polymorphisms (Y-SNPs) and Y-chromosomal short tandem repeats (Y-STRs). In a test using DNA samples from 706 Korean males, a total of 19 different haplogroups were identified by 26 Y-SNPs including the newly redefined markers ...
Moghadam Hooman K - - 2012
The W chromosome is predicted to be subject to strong female-specific selection stemming from its female-limited inheritance and therefore should play an important role in female fitness traits. However, the overall importance of directional selection in shaping the W chromosome is unknown because of the powerful degradative forces that act ...
Celestino-Soper Patrícia B S - - 2012
We recently reported a deletion of exon 2 of the trimethyllysine hydroxylase epsilon (TMLHE) gene in a proband with autism. TMLHE maps to the X chromosome and encodes the first enzyme in carnitine biosynthesis, 6-N-trimethyllysine dioxygenase. Deletion of exon 2 of TMLHE causes enzyme deficiency, resulting in increased substrate concentration ...
Ghorbian Saeid - - 2012
Male factor infertility elucidated about half the couple of infertility and in around 50% of cases, its etiology remains unknown. The aim of this study was to investigate a predisposing genetic background for Yq deletions and male infertility and effectiveness of molecular genetic approaches have uncovered several etiopathogenetic factors, such ...
Menon Debashish U - - 2012
Sex-chromosome dosage compensation requires selective identification of X chromatin. How this occurs is not fully understood. We show that small interfering RNA (siRNA) mutations enhance the lethality of Drosophila males deficient in X recognition and partially rescue females that inappropriately dosage-compensate. Our findings are consistent with a role for siRNA ...
Mokánszki Attila - - 2012
Male carriers with balanced reciprocal translocations can produce a variable proportion of unbalanced gametes resulting in reproductive failures. The presence of a structural rearrangement may induce an interchromosomal effect. This is characterized by abnormal bivalents not involved in the reorganization thereby yielding non-disjunction, which would present as aneuploid spermatozoa for ...
Almeida Carolina - - 2012
Carriers of balanced structural chromosomal abnormalities are phenotypically normal but are at high risk of infertility. Translocations usually occur between two non-homologous chromosomes. When occur between homologous chromosomes, an extremely rare event, generally involve acrocentric chromosomes. We present an infertile male referred for genetic analysis with a pure balanced homologous ...
Wang Jun - - 2012
Previous studies on organisms with well-differentiated X and Y chromosomes, such as Drosophila and mammals, consistently detected an excess of genes moving out of the X chromosome and gaining testis-biased expression. Several selective evolutionary mechanisms were shown to be associated with this nonrandom gene traffic, which contributed to the evolution ...
Cavkaytar Sabri - - 2012
Abstract Objective: To determine the frequency, types of chromosomal abnormalities and Y chromosome microdeletions in patients with severe male factor infertility, and the association between clinical background and genetic abnormality. Study Design: A total of 322 infertile men; 136 men with severe oligozoospermia (sperm count < 5million/ml) and 196 with ...
Navarro-Costa Paulo - - 2012
It can be argued that the Y chromosome brings some of the spirit of rock&roll to our genome. Equal parts degenerate and sex-driven, the Y has boldly rebelled against sexual recombination, one of the sacred pillars of evolution. In evolutionary terms this chromosome also seems to have adopted another of ...
Zandman-Goddard Gisele - - 2012
New evidence suggesting an X chromosome effect underlies the development and progression of male systemic lupus erythematosus comes from a study of sex chromosome aneuploidy in men with this disease. The description of a number of immunoregulatory mechanisms encoded on the X chromosome support this hypothesis; however, further studies are ...
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