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1.
Cytogenet Genome Res ; 153(2): 66-72, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29248929

RESUMO

Unbalanced translocations involving X and Y chromosomes are rare and associated with a contiguous gene syndrome. The clinical phenotype is heterogeneous including mainly short stature, chondrodysplasia punctata, ichthyosis, hypogonadism, and intellectual disability. Here, we report 2 brothers with peculiar gestalt, short stature, and hearing loss, who harbor an X/Y translocation. Physical examination, brainstem acoustic potential evaluation, bone age, hormonal assessment, and X-ray investigations were performed. Because of their dysmorphic features, karyotyping, FISH, and aCGH were carried out. The probands had short stature, hypertelorism, midface hypoplasia, sensorineural hearing loss, normal intelligence as well as slight radial and ulnar bowing with brachytelephalangy. R-banding identified a derivative X chromosome with an abnormally expanded short arm. The mother was detected as a carrier of the same aberrant X chromosome. aCGH disclosed a 3.1-Mb distal deletion of chromosome region Xp22.33pter. This interval encompasses several genes, especially the short stature homeobox (SHOX) and arylsulfatase (ARSE) genes. The final karyotype of the probands was: 46,Y,der(X),t(X;Y)(p22;q12).ish der(X)(DXYS129-,DXYS153-)mat.arr[hg19] Xp22.33(61091_2689408)×1mat,Xp22.33(2701273_3258404)×0mat,Yq11.222q12 (21412851_59310245)×2. Herein, we describe a Moroccan family with a maternally inherited X/Y translocation and discuss the genotype-phenotype correlations according to the deleted genes.


Assuntos
Anormalidades Múltiplas/genética , Arilsulfatases/genética , Cromossomos Humanos X/genética , Cromossomos Humanos Y/genética , Perda Auditiva Bilateral/genética , Perda Auditiva Neurossensorial/genética , Translocação Genética , Arilsulfatases/deficiência , Cromossomos Humanos X/ultraestrutura , Cromossomos Humanos Y/ultraestrutura , Consanguinidade , Feminino , Humanos , Hipertelorismo/genética , Recém-Nascido , Cariotipagem , Masculino , Pessoa de Meia-Idade , Marrocos , Linhagem , Fenótipo , Rádio (Anatomia)/anormalidades , Escoliose/genética , Irmãos , Ulna/anormalidades , Adulto Jovem
2.
Cytogenet Genome Res ; 153(4): 190-197, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29466784

RESUMO

To investigate the clinical, hormonal, and genetic factors in infertile men with idiopathic nonobstructive azoospermia (NOA) or azoospermic Klinefelter syndrome (KFS), a total of 556 and 96 patients, respectively, were included in this study. All patient samples were analyzed cytogenetically. Serum reproductive hormone levels were measured. Microdeletions in the azoospermia factor (AZF) region of the Y chromosome were detected by multiplex PCR using 16 specific sequence-tagged sites. FSH and LH levels in both NOA and KFS patients were significantly higher than the normal range, and the testosterone level in KFS patients was significantly lower. Ninety-two (95.8%) of the KFS patients showed non-mosaic 47,XXY karyotypes and 47,XXY,inv(9)(p11.1q13); the other KFS patients had mosaic karyotypes of 47,XXY/46,XY, 47,XXY/46,XX, and 47,XXY/48,XXXY/46,XX. Among the 556 idiopathic NOA patients with normal karyotypes, 67 (12.05%) had microdeletions in the AZF region of the Y chromosome. Microdeletions were most frequently detected in the AZFc region, followed by AZFa, AZFb, AZFbc, and partial AZFc deletions. However, Y chromosome microdeletions were not found in any of the azoospermic KFS patients. In view of the hormonal and genetic abnormalities in infertile men with idiopathic NOA and with azoospermic KFS, genetic testing for karyotype, Y chromosome microdeletions, and hormonal parameters is advocated.


Assuntos
Azoospermia/genética , Hormônios Esteroides Gonadais/sangue , Gonadotropinas Hipofisárias/sangue , Síndrome de Klinefelter/genética , Cariótipo Anormal , Adulto , Idoso , Aneuploidia , Azoospermia/sangue , Azoospermia/patologia , Cromossomos Humanos Y/genética , Cromossomos Humanos Y/ultraestrutura , Humanos , Infertilidade Masculina/etiologia , Cariotipagem , Síndrome de Klinefelter/sangue , Síndrome de Klinefelter/patologia , Masculino , Pessoa de Meia-Idade , Mosaicismo , Tamanho do Órgão , Análise do Sêmen , Deleção de Sequência , Testículo/patologia , Adulto Jovem
3.
Eur J Pediatr Surg ; 26(3): 273-6, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25978024

RESUMO

The presence of the Y chromosome in the karyotype of patients with disorders of sex differentiation is significantly associated with an increased risk to develop specific types of malignancies, predominantly type II germ cell tumors (GCTs). Gonadoblastoma in the gonads without an obvious testicular differentiation and intratubular germ cell neoplasia of unclassified type in testicular tissue are the precursor lesions of most GCTs. Gonadal dysgenesis, the characteristic feature of Ullrich-Turner syndrome (UTS), further contributes to increase this tumor risk. The reported incidence of Y chromosome material in UTS is 6 to 8% and in these cases an early gonadectomy is strongly recommended to prevent the risk of a malignancy. The aim of this work was to retrospectively analyze the clinical outcome and the histopathological and cytogenetic findings of our UTS patients who underwent gonadectomy to establish strict selection criteria aimed at promoting an organ-sparing surgery.


Assuntos
Cromossomos Humanos Y/genética , Disgerminoma/patologia , Gonadoblastoma/patologia , Gônadas/cirurgia , Neoplasias Ovarianas/patologia , Síndrome de Turner/complicações , Síndrome de Turner/genética , Adolescente , Proteínas de Ciclo Celular/genética , Criança , Cromossomos Humanos Y/ultraestrutura , Disgerminoma/genética , Disgerminoma/cirurgia , Feminino , Predisposição Genética para Doença , Gonadoblastoma/complicações , Gonadoblastoma/genética , Gonadoblastoma/cirurgia , Gônadas/patologia , Humanos , Cariotipagem , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/cirurgia , Procedimentos Cirúrgicos Profiláticos , Estudos Retrospectivos , Fatores de Risco , Fatores de Transcrição SOXB1/genética , Síndrome de Turner/patologia
4.
Hum Reprod ; 29(7): 1413-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24826988

RESUMO

STUDY QUESTION: What is the optimal protocol of management for phenotypic female patients with Y chromosome or Y-derived sequences, in particular for adult patients? SUMMARY ANSWER: Immediate gonadectomy, long-term hormone therapy and psychological care are suggested to be the optimal management for older phenotypic female patients with Y chromosome or Y-derived sequences. WHAT IS KNOWN ALREADY: Phenotypic female patients with Y chromosome or Y-derived sequences are at increasing risk of developing gonadal tumors with age. Early diagnosis and safe guidelines of management for these patients are needed. STUDY DESIGN, SIZE, DURATION: One hundred and two phenotypic women with Y chromosome or Y-derived sequences were included in a straightforward, retrospective-observational study conducted over a period of 26 years from January 1985 to November 2010. PARTICIPANTS/MATERIALS, SETTING AND METHODS: Patients aged 16-34 years presenting to our Academic Department of Gynecology with symptoms of disorders of sex development were subjected to history taking, hormonal evaluation, conventional cytogenetic analysis, PCR, histopathology and immunohistochemistry. Features of the gonads were examined and the outcome of prophylactic gonadectomy evaluated. MAIN RESULTS AND THE ROLE OF CHANCE: Among the patients recruited in our study, 48 patients (47.1%) were diagnosed with complete/partial androgen insensitivity syndrome (CAIS/PAIS) (46XY), 33 cases (32.4%) with gonadal dysgenesis (46XY) and the remaining subjects (20.1%) with mixed gonadal dysgenesis (with sex chromosome structural abnormalities). The total incidence of malignancy was 17.6%. Seventeen patients (16.7%) had gonadoblastoma, while one patient (1.0%) with gonadal dysgenesis had dysgerminoma. Gonadoblastoma were observed in 2/21 patients with sex chromosome structural abnormalities (9.5%), 3/33 patients with gonadal dysgenesis (9.1%), 9/30 patients with CAIS (30.0%) and 3/18 patients with PAIS (16.7%). LIMITATIONS, REASONS FOR CAUTION: Selection bias in this cohort study may affect data interpretation due to the low incidence of disorders of sex development in the general population. WIDER IMPLICATIONS OF THE FINDINGS: The risk for malignant transformation may occur in early life and highly increase with age in patients with Y chromosome or Y-derived sequences. Optimal timing of gonadectomy should be decided by multiple factors including the subgroup of disorder, age and degree of patient's maturity. In addition, gonadal biopsy is suggested when the disease is diagnosed and any evidence of premalignancy warranties gonadectomy. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Key Scientific Research Project (2013CB967404), Natural Science Funds of Zhejiang Province (Y13H04005), Zhejiang Qianjiang talent plan (2013R10027), the Fundamental Research Funds for the Central Universities and Key Projects in the National Science & Technology Pillar Program during the Eleventh Five-Year Plan Period (2012BAI32B04). The authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER None.


Assuntos
Cromossomos Humanos Y/ultraestrutura , Transtornos Gonadais/genética , Gonadoblastoma/genética , Adolescente , Adulto , Síndrome de Resistência a Andrógenos/diagnóstico , Síndrome de Resistência a Andrógenos/genética , Aberrações Cromossômicas , Citogenética , Feminino , Genitália/patologia , Transtornos Gonadais/diagnóstico , Transtornos Gonadais/cirurgia , Disgenesia Gonadal/diagnóstico , Disgenesia Gonadal/genética , Gonadoblastoma/diagnóstico , Gonadoblastoma/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Fenótipo , Estudos Retrospectivos , Risco , Fatores Sexuais , Adulto Jovem
5.
Ann Endocrinol (Paris) ; 75(2): 112-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24786699

RESUMO

Infertility affects 15% of couples at reproductive age and human male infertility appears frequently idiopathic. The main genetic causes of spermatogenesis defect responsible for non-obstructive azoospermia and severe oligozoospermia are constitutional chromosomal abnormalities and microdeletions in the azoospermia factor region of the Y chromosome. The improvement of the Yq microdeletion screening method gave new insights in the mechanism responsible for the genesis of Yq microdeletions and for the consequences of the management of male infertility and genetic counselling in case of assisted reproductive technology.


Assuntos
Cromossomos Humanos Y/genética , Aconselhamento Genético , Infertilidade Masculina/genética , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Deleção Cromossômica , Cromossomos Humanos Y/ultraestrutura , Gerenciamento Clínico , Testes Genéticos , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/psicologia , Masculino , Técnicas de Reprodução Assistida , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/terapia , Espermatogênese/genética
6.
Ann Endocrinol (Paris) ; 75(2): 109-11, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24768008

RESUMO

Male infertility, affecting around half of the couples with a problem to get pregnant, is a very heterogeneous condition. Part of patients are having a defect in spermatogenesis of which the underlying causes (including genetic ones) remain largely unknown. The only genetic tests routinely used in the diagnosis of male infertility are the analyses for the presence of Yq microdeletions and/or chromosomal abnormalities. Various other single gene or polygenic defects have been proposed to be involved in male fertility. Yet, their causative effect often remains to be proven. The recent evolution in the development of whole genome-based techniques may help in clarifying the role of genes and other genetic factors involved in spermatogenesis and spermatogenesis defects.


Assuntos
Infertilidade Masculina/genética , Azoospermia/diagnóstico , Azoospermia/genética , Causalidade , Aberrações Cromossômicas , Deleção Cromossômica , Cromossomos Humanos Y/genética , Cromossomos Humanos Y/ultraestrutura , Hibridização Genômica Comparativa/métodos , Análise Mutacional de DNA/métodos , Predisposição Genética para Doença , Testes Genéticos , Humanos , Infertilidade Masculina/diagnóstico , Síndrome de Klinefelter/diagnóstico , Síndrome de Klinefelter/genética , Masculino , Polimorfismo de Nucleotídeo Único , Deleção de Sequência , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Espermatogênese/genética
7.
Syst Biol Reprod Med ; 59(4): 223-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23631693

RESUMO

The human ejaculate contains subpopulations of sperm with distinct properties. Human X- and Y-bearing sperm were separated with fluorescence activated cell sorting. To avoid the use of UV light the quantitative DNA dyes DRAQ5® and Dyecycle™ Vybrant® Violet were used. Sorting efficiency was similar for both dyes, but lower than what is usually obtained with the classical method involving Hoechst 33342 and UV light (60-70% enrichment, versus 80-90%). A total of 2,739 spermatozoa were evaluated, from seven distinct samples using fluorescence in situ hybridization (FISH) chromosomal probes. No differences were found in sorted and unsorted populations in terms of chromosome positioning, and numeric chromosomal anomalies were not more evident following cell sorting. Furthermore in both sorted and unsorted populations the sex chromosomes were clearly located in the anterior portion of the sperm head, while a control autosome (chromosome 18) showed no such tendency, confirming previous findings. These results suggest that other quantitative DNA dyes may be used for sex chromosome-based human sperm sorting, but with lower efficiency than the standard UV-Hoechst based assay.


Assuntos
Cromossomos Humanos X/ultraestrutura , Cromossomos Humanos Y/ultraestrutura , Citometria de Fluxo/métodos , Cabeça do Espermatozoide/ultraestrutura , Espermatozoides/citologia , Antraquinonas , Separação Celular/métodos , Corantes , Humanos , Hibridização in Situ Fluorescente , Masculino
8.
Actas Urol Esp ; 37(5): 266-72, 2013 May.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-23062736

RESUMO

INTRODUCTION: Testicular sperm extraction with intracytoplasmic sperm injection is the standard treatment for azoospermia. The objective of this study is to identify predictive factors of successful sperm retrieval. MATERIALS AND METHODS: Between June 2003 and May 2011, we tried testicular sperm extraction (TESE) in 74 azoospermic patients in the Reproductive Medicine Unit of Son Espases Hospital (Palma de Mallorca). Serum follicle stimulating hormone (FSH) and inhibin B levels, testicular histology, genetic study, presence or not of cryptozoospermia and testicular volume were examined. RESULTS: Spermatozoa were successfully recovered in 47.2% of the total patients, in 36% of non-obstructive azoospermic patients and in 100% of obstructive azoospermic patients. Low inhibin B and high FSH were correlated to sperm retrieval failure. The cutoff points were determined using ROC curves that were 67 pg/mL for inhibin B and 12.2 mUI/mL for FSH. Spermatozoa were not successfully retrieved in any patient with Y microdeletions in AZFa,b regions. Spermatozoa were successfully retrieved in 100% of the patients with CFTR mutations. The highest sperm retrieval rate was for hypospermatogenesis, followed by maturation arrest and Sertoli-cell-only. Spermatozoa were successfully retrieved in all cryptozoospermic patients. Although using a non-significant test, there seems to be a correlation between higher testicular volume and a higher probability of successful sperm retrieval. CONCLUSIONS: Except for Y microdeletions in AZFa,b regions, there is no predictive factor of testicular sperm retrieval to rule out a patient for TESE. Lower inhibin B is more related to sperm retrieval failure than higher FSH. Sperm retrieval is possible for all cases of CFTR mutations but in any case of microdeletion Y in AZFa,b. The lack of germ cells is correlated with a high probability of sperm retrieval failure. The presence of cryptozoospermia is correlated with a high probability of sperm retrieval success. We do not find a statistically significant relation between testicular volume and successful sperm retrieval.


Assuntos
Azoospermia/patologia , Injeções de Esperma Intracitoplásmicas , Espermatozoides , Adulto , Azoospermia/sangue , Centrifugação , Deleção Cromossômica , Cromossomos Humanos Y/ultraestrutura , Regulador de Condutância Transmembrana em Fibrose Cística/deficiência , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Hormônio Foliculoestimulante/sangue , Humanos , Inibinas/sangue , Cariotipagem , Masculino , Tamanho do Órgão , Análise do Sêmen , Aberrações dos Cromossomos Sexuais , Manejo de Espécimes , Contagem de Espermatozoides , Maturação do Esperma , Espermatogênese , Testículo/patologia
9.
PLoS One ; 7(11): e50206, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209673

RESUMO

The human populations of the Iberian Peninsula are the varied result of a complex mixture of cultures throughout history, and are separated by clear social, cultural, linguistic or geographic barriers. The stronger genetic differences between closely related populations occur in the northern third of Spain, a phenomenon commonly known as "micro-differentiation". It has been argued and discussed how this form of genetic structuring can be related to both the rugged landscape and the ancient societies of Northern Iberia, but this is difficult to test in most regions due to the intense human mobility of previous centuries. Nevertheless, the Spanish autonomous community of Asturias shows a complex history which hints of a certain isolation of its population. This, joined together with a difficult terrain full of deep valleys and steep mountains, makes it suitable for performing a study of genetic structure, based on mitochondrial DNA and Y-Chromosome markers. Our analyses do not only show that there are micro-differentiation patterns inside the Asturian territory, but that these patterns are strikingly similar between both uniparental markers. The inference of barriers to gene flow also indicates that Asturian populations from the coastal north and the mountainous south seem to be relatively isolated from the rest of the territory. These findings are discussed in light of historic and geographic data and, coupled with previous evidence, show that the origin of the current genetic patterning might indeed lie in Roman and Pre-Roman sociopolitical divisions.


Assuntos
Cromossomos Humanos Y/ultraestrutura , DNA Mitocondrial/genética , Política , Características Culturais , DNA Mitocondrial/metabolismo , Feminino , Frequência do Gene , Variação Genética , Genética Populacional , Geografia , Haplótipos , Humanos , Masculino , Modelos Genéticos , Filogenia , Análise de Sequência de DNA , Espanha
10.
Hum Reprod ; 27(9): 2607-12, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22752611

RESUMO

BACKGROUND: Fetal cells (microchimerism) are acquired by women during pregnancy. Fetal microchimerism persists decades later and includes cells with pluripotent capacity. Persistent microchimerism has the capacity for both beneficial and detrimental maternal health consequences. Both miscarriage and termination of pregnancy can result in fetal microchimerism. We sought to determine whether cellular fetal microchimerism is acquired during management of pregnancy loss and further explored factors that could influence fetal cell transfer, including viability of fetal tissue, surgical versus medical management and gestational age. METHODS: Pregnant women (n= 150 samples from 75 women) with singleton pregnancies undergoing a TOP (n= 63) or treatment for embryonic or fetal demise (miscarriage, n= 12) were enrolled. Mononuclear cells were isolated from blood samples drawn before, and 30 min after, treatment. Fetal cellular microchimerism concentrations were determined using quantitative PCR for a Y chromosome-specific sequence, expressed as genome equivalents of fetal DNA per 100 000 maternal cell equivalents (gEq/10(5)). Detection rate ratios were determined according to clinical characteristics. RESULTS: Cellular fetal microchimerism was found more often in post- compared with pretreatment samples, 24 versus 5% (P= 0.004) and at higher concentrations, 0-36 versus 0-0.7 gEq/10(5) (P< 0.001). Likelihood of microchimerism was higher in surgical than medical management, detection rate ratio 24.7 (P= 0.02). The detection rate ratio for TOP versus miscarriage was 16.7 for known male fetuses (P= 0.02). Microchimerism did not vary with gestational age. CONCLUSIONS: Significant fetal cell transfer occurs during miscarriage and TOP. Exploratory analyses support relationships between obstetric clinical factors and acquisition of fetal cellular microchimerism; however, our limited sample size precludes definitive analysis of these relationships, and confirmation is needed. In addition, the long-term persistence and potential consequences of fetal microchimerism on maternal health merit further investigation.


Assuntos
Aborto Induzido , Aborto Espontâneo/diagnóstico , Quimerismo , Aborto Espontâneo/genética , Adolescente , Adulto , Cromossomos Humanos Y/ultraestrutura , Estudos de Coortes , Feminino , Feto , Idade Gestacional , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/patologia , Masculino , Troca Materno-Fetal , Reação em Cadeia da Polimerase/métodos , Gravidez , Estudos Prospectivos
11.
Hum Reprod ; 27(9): 2857-65, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22752612

RESUMO

BACKGROUND: Deleted in AZoospermia-like (DAZL) is an autosomal homologue of Y chromosome-linked DAZ gene located on chromosome 3p24. DAZL is only expressed in the gonads and is critical to germ cell development in different species. However, the regulation of DAZL has not been explored. METHODS: Reporter assays, electrophoretic mobility shift assays, supershift assays and bisulfate sequencing were used to identify the core promoter region of DAZL. Sequence analysis was used to identify single-nucleotide polymorphisms (SNPs) in the promoter region. A total of 337 infertile men with abnormal semen parameters and 203 fertile men with normal semen parameters were subjected to sequence analysis of the DAZL promoter region. RESULTS: The DAZL gene core promoter is located 1 kb upstream of the transcription start site. Three SNPs (-792G>A, -669A>C and -309T>C) were identified in our population. Of these three SNPs, -792G>A was more prevalent in the infertile men (P= 0.0005). Quantitative analysis revealed that genotypes of -792G>A had effects on sperm concentration (P= 0.0025) and motility (P= 1.5 × 10(-7)). The G to A substitution was associated with decreased binding of the nuclear respiratory factor-1 (NRF-1) to the promoter region and decreased reporter gene activity. CONCLUSION: We have identified the core promoter of the human DAZL gene. We also provide preliminary evidence for the role of a novel SNP of the DAZL gene promoter in human spermatogenic failure.


Assuntos
Regulação da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/genética , Espermatogênese/genética , Alelos , Cromossomos Humanos Y/ultraestrutura , Frequência do Gene , Genes Reporter , Predisposição Genética para Doença , Células HeLa , Humanos , Infertilidade Masculina/genética , Masculino , Mutação , Análise de Sequência de DNA , Taiwan
13.
Syst Biol Reprod Med ; 57(1-2): 93-101, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21204593

RESUMO

Since the early 1990s male infertility has successfully been treated by intracytoplasmic sperm injection (ICSI), nevertheless concerns have been raised regarding the genetic risk of ICSI. Chromosome aneuploidy (the presence of extra or missing chromosomes) is the leading cause of pregnancy loss and mental retardation in humans. While the majority of chromosome aneuploidies are maternal in origin, the paternal contribution to aneuploidy is clinically relevant particularly for the sex chromosomes. Given that it is difficult to study female gametes investigations are predominantly conducted in male meiotic recombination and sperm aneuploidy. Research suggests that infertile men have increased levels of sperm aneuploidy and that this is likely due to increased errors in meiotic recombination and chromosome synapsis within these individuals. It is perhaps counterintuitive but there appears to be no selection against chromosomally aneuploid sperm at fertilization. In fact the frequency of aneuploidy in sperm appears to be mirrored in conceptions. Given this information this review will cover our current understanding of errors in meiotic recombination and chromosome synapsis and how these may contribute to increased sperm aneuploidy. Frequencies of sperm aneuploidy in infertile men and individuals with constitutional karyotypic abnormalities are reviewed, and based on these findings, indications for clinical testing of sperm aneuploidy are discussed. In addition, the application of single nucleotide arrays for the analysis of meiotic recombination and identification of parental origin of aneuploidy are considered.


Assuntos
Aneuploidia , Infertilidade Masculina/genética , Meiose , Recombinação Genética , Aberrações Cromossômicas/estatística & dados numéricos , Cromossomos Humanos X/ultraestrutura , Cromossomos Humanos Y/ultraestrutura , Feminino , Humanos , Masculino , Gravidez , Taxa de Gravidez , Injeções de Esperma Intracitoplásmicas , Espermatozoides , Complexo Sinaptonêmico/fisiologia
14.
Chromosome Res ; 19(1): 5-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21190132

RESUMO

The optical resolution of conventional far field fluorescence light microscopy is restricted to about 200 nm laterally and 600 nm axially and has been thought for many decades to be an insurmountable barrier for the quantitative spatial analysis of cellular and hence also nuclear constituents. Novel approaches in light microscopy have now overcome this barrier. Here, we report on a special method of localisation microscopy, spectral precision distance/position determination microscopy and its combination with fluorescence in situ hybridization to analyse the spatial distribution of specific DNA sequences in human cell nuclei at the macromolecular optical resolution level. As an example, repetitive DNA sequence DYZ2 located within the heterochromatin region on human chromosome Yq12 was labelled with clone pHY2.1. Between 300 and 700 single-probe molecules were resolved in individual chromatin domains, corresponding to a detected molecule density around 500/µm(2), i.e., many times higher than resolvable by conventional fluorescence microscopy. A mean localisation accuracy of about 20 nm indicated a mean optical resolution in the 50 nm range. Beyond new perspectives for light microscopic studies of specific chromatin nanostructures, this may open a new avenue towards the general analysis of copy number of specific DNA sequences in small regions of individual interphase nuclei.


Assuntos
Heterocromatina/ultraestrutura , Hibridização in Situ Fluorescente/métodos , Microscopia de Fluorescência/métodos , Microscopia/métodos , Linhagem Celular , Núcleo Celular/ultraestrutura , Cromossomos Humanos Y/ultraestrutura , DNA/genética , Processamento Eletrônico de Dados , Fibroblastos , Genoma Humano , Humanos , Nanoestruturas/química
15.
PLoS One ; 5(12): e15283, 2010 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-21187967

RESUMO

BACKGROUND: The geographical position of Maharashtra state makes it rather essential to study the dispersal of modern humans in South Asia. Several hypotheses have been proposed to explain the cultural, linguistic and geographical affinity of the populations living in Maharashtra state with other South Asian populations. The genetic origin of populations living in this state is poorly understood and hitherto been described at low molecular resolution level. METHODOLOGY/PRINCIPAL FINDINGS: To address this issue, we have analyzed the mitochondrial DNA (mtDNA) of 185 individuals and NRY (non-recombining region of Y chromosome) of 98 individuals belonging to two major tribal populations of Maharashtra, and compared their molecular variations with that of 54 South Asian contemporary populations of adjacent states. Inter and intra population comparisons reveal that the maternal gene pool of Maharashtra state populations is composed of mainly South Asian haplogroups with traces of east and west Eurasian haplogroups, while the paternal haplogroups comprise the South Asian as well as signature of near eastern specific haplogroup J2a. CONCLUSIONS/SIGNIFICANCE: Our analysis suggests that Indian populations, including Maharashtra state, are largely derived from Paleolithic ancient settlers; however, a more recent (∼10 Ky older) detectable paternal gene flow from west Asia is well reflected in the present study. These findings reveal movement of populations to Maharashtra through the western coast rather than mainland where Western Ghats-Vindhya Mountains and Narmada-Tapti rivers might have acted as a natural barrier. Comparing the Maharastrian populations with other South Asian populations reveals that they have a closer affinity with the South Indian than with the Central Indian populations.


Assuntos
DNA Mitocondrial/genética , Genética Populacional , Haplótipos , Algoritmos , Ásia , Cromossomos Humanos Y/ultraestrutura , Etnicidade , Geografia , Humanos , Índia , Repetições de Microssatélites , Modelos Genéticos , Modelos Estatísticos , Filogenia , Análise de Componente Principal
16.
Proc Natl Acad Sci U S A ; 107(15): 6759-64, 2010 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-20351276

RESUMO

The Farming/Language Dispersal Hypothesis posits that prehistoric population expansions, precipitated by the innovation or early adoption of agriculture, played an important role in the uneven distribution of language families recorded across the world. In this case, the most widely spread language families today came to be distributed at the expense of those that have more restricted distributions. In the Americas, Uto-Aztecan is one such language family that may have been spread across Mesoamerica and the American Southwest by ancient farmers. We evaluated this hypothesis with a large-scale study of mitochondrial DNA (mtDNA) and Y-chromosomal DNA variation in indigenous populations from these regions. Partial correlation coefficients, determined with Mantel tests, show that Y-chromosome variation in indigenous populations from the American Southwest and Mesoamerica correlates significantly with linguistic distances (r = 0.33-0.384; P < 0.02), whereas mtDNA diversity correlates significantly with only geographic distance (r = 0.619; P = 0.002). The lack of correlation between mtDNA and Y-chromosome diversity is consistent with differing population histories of males and females in these regions. Although unlikely, if groups of Uto-Aztecan speakers were responsible for the northward spread of agriculture and their languages from Mesoamerica to the Southwest, this migration was possibly biased to males. However, a recent in situ population expansion within the American Southwest (2,105 years before present; 99.5% confidence interval = 1,273-3,773 YBP), one that probably followed the introduction and intensification of maize agriculture in the region, may have blurred ancient mtDNA patterns, which might otherwise have revealed a closer genetic relationship between females in the Southwest and Mesoamerica.


Assuntos
Cromossomos Humanos Y/ultraestrutura , DNA Mitocondrial/ultraestrutura , Variação Genética , Indígenas Norte-Americanos/genética , Idioma , Agricultura/métodos , Evolução Biológica , América Central , Emigração e Imigração , Etnicidade/genética , Feminino , Genética Populacional , História Antiga , Humanos , Indígenas Norte-Americanos/história , Masculino , Dados de Sequência Molecular , Fatores Sexuais , Sudoeste dos Estados Unidos , Zea mays/metabolismo
17.
Am J Hum Genet ; 85(6): 923-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20004767

RESUMO

Y-linked single-nucleotide polymorphisms (SNPs) have served as powerful tools for reconstructing the worldwide genealogy of human Y chromosomes and for illuminating patrilineal relationships among modern human populations. However, there has been no systematic, worldwide survey of sequence variation within the protein-coding genes of the Y chromosome. Here we report and analyze coding sequence variation among the 16 single-copy "X-degenerate" genes of the Y chromosome. We examined variation in these genes in 105 men representing worldwide diversity, resequencing in each man an average of 27 kb of coding DNA, 40 kb of intronic DNA, and, for comparison, 15 kb of DNA in single-copy Y-chromosomal pseudogenes. There is remarkably little variation in X-degenerate protein sequences: two chromosomes drawn at random differ on average by a single amino acid, with half of these differences arising from a single, conservative Asp-->Glu mutation that occurred approximately 50,000 years ago. Further analysis showed that nucleotide diversity and the proportion of variant sites are significantly lower for nonsynonymous sites than for synonymous sites, introns, or pseudogenes. These differences imply that natural selection has operated effectively in preserving the amino acid sequences of the Y chromosome's X-degenerate proteins during the last approximately 100,000 years of human history. Thus our findings are at odds with prominent accounts of the human Y chromosome's imminent demise.


Assuntos
Cromossomos Humanos Y/genética , Cromossomos Humanos Y/ultraestrutura , Polimorfismo de Nucleotídeo Único , Cromossomos/ultraestrutura , DNA/genética , Deleção de Genes , Variação Genética , Humanos , Íntrons , Masculino , Modelos Genéticos , Nucleotídeos/genética , Seleção Genética , Análise de Sequência de DNA
18.
J Assist Reprod Genet ; 26(5): 291-5, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19440834

RESUMO

AIM: To describe the case of a 32-year-old infertile male with small supernumerary marker chromosome (sSMCs) in 80% of peripheral lymphocytes. METHODS: G-banding, C-banding, STRP analysis, M-FISH and molecule diagnosis of Y-chromosomal microdeletions were performed to determine the origin of sSMCs. RESULTS: The karyotype of this patient was established as 47, XY, +mar/46, XY. C-banding showed that the marker chromosome was composed of heterochromatin without visible euchromatic material. No positive result was obtained in STRP, M-FISH and the microdeletion analysis of Y- chromosome. CONCLUSIONS: The small supernumerary marker chromosome could play a causative role in male infertility although the mechanism remains to be elucidated.


Assuntos
Marcadores Genéticos/genética , Heterocromatina/genética , Hibridização in Situ Fluorescente/métodos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética , Adulto , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Y/ultraestrutura , Primers do DNA/genética , Humanos , Cariotipagem , Linfócitos/metabolismo , Masculino , Repetições de Microssatélites/genética , Polimorfismo Genético
19.
Asian J Androl ; 10(6): 873-81, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18958351

RESUMO

AIM: To develop a high-throughput multiplex, fast and simple assay to scan azoospermia factor (AZF) region microdeletions on the Y chromosome and establish the prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. METHODS: In total, 178 infertile patients with azoospermia (non-obstructed), 134 infertile patients with oligozoospermia as well as 40 fertile man controls were included in the present study. The samples were screened for AZF microdeletion using optimized multi-analyte suspension array (MASA) technology. RESULTS: Of the 312 patients, 36 (11.5%) were found to have deletions in the AZF region. The microdeletion frequency was 14% (25/178) in the azoospermia group and 8.2% (11/134) in the oligospermia group. Among 36 patients with microdeletions, 19 had deletions in the AZFc region, seven had deletions in AZFa and six had deletions in AZFb. In addition, four patients had both AZFb and AZFc deletions. No deletion in the AZF region was found in the 40 fertile controls. CONCLUSION: There is a high prevalence of Y chromosomal microdeletions in Chinese infertile males with azoospermia or oligozoospermia. The MASA technology, which has been established in the present study, provides a sensitive and high-throughput method for detecting the deletion of the Y chromosome. And the results suggest that genetic screening should be advised to infertile men before starting assisted reproductive treatments.


Assuntos
Azoospermia/epidemiologia , Azoospermia/genética , Cromossomos Humanos Y/genética , Cromossomos Humanos Y/ultraestrutura , Deleção de Genes , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/genética , Proteínas de Plasma Seminal/genética , Adulto , China/epidemiologia , DNA/genética , DNA/isolamento & purificação , Feminino , Loci Gênicos , Gliceraldeído-3-Fosfato Desidrogenases/genética , Humanos , Hibridização In Situ , Masculino , Sondas de Oligonucleotídeos , Oligospermia/epidemiologia , Oligospermia/genética , Oligospermia/metabolismo , Análise Serial de Proteínas , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Indian J Med Res ; 127(2): 124-32, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18403789

RESUMO

BACKGROUND & OBJECTIVE: Analysis of the microdeletions in the azoospermia factor (AZF) region of Y chromosome by PCR is an important screening tool in the work-up of infertile males opting for assisted reproductive techniques. In the present study, the Y chromosome microdeletions were analyzed by PCR using primers corresponding to 16 sequence tagged sites (STS) and three genes of the AZF region in infertile Indian men. Feasibility of developing a simplified multiplex PCR for screening of the Y chromosome microdeletions has been explored. METHODS: A total of 271 male subjects were analyzed, of which, 170 were infertile patients (51 oligospermic and 119 azoospermic) and 101 were fertile controls. Subjects showing normal karyotype only were included in the study. The semen analysis was done and plasma follicle stimulating hormone (FSH) concentrations were determined by radioimmunoassay. Testicular histopathology was analyzed by fine needle aspiration cytology (FNAC). RESULTS: Y chromosome microdeletions were observed in nine out of 170 (5.29%) infertile males all of whom were azoospermic. Of the nine subjects, two had deletions in AZFa, one in AZFb, three in AZFc and three in AZFb+c regions. No deletions were observed in the infertile severe oligospermic men (< 5 million sperm/ml semen) and fertile controls. No difference in the FSH concentrations of infertile patients with and without deletions (18.36 and 18.10 mIU/ml respectively) was observed. A clear relationship between Y chromosome microdeletions and testicular phenotypes could not be established. Two multiplex PCRs were designed using 7 STSs markers, which could detect Y chromosome microdeletions in infertile male subjects as efficiently as PCR based on larger number of PCR reactions. INTERPRETATION & CONCLUSION: The multiplex PCRs described in the present study may be a suitable, cost-effective and less time consuming method for screening the Y chromosome deletions in infertile males in routine clinical diagnosis and counselling prior to assisted reproduction.


Assuntos
Cromossomos Humanos Y/ultraestrutura , Deleção de Genes , Infertilidade Masculina/genética , Adulto , Azoospermia/genética , Estudos de Casos e Controles , Cromossomos Humanos Y/genética , Hormônio Foliculoestimulante/metabolismo , Humanos , Índia , Cariotipagem , Masculino , Oligospermia/genética , Radioimunoensaio/métodos , Sitios de Sequências Rotuladas , Aberrações dos Cromossomos Sexuais
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