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1.
Cancer Treat Res ; 187: 237-259, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37851231

RESUMEN

Judaism offers a rich body of traditional beliefs and practices surrounding end-of-life, death, mourning, and the afterlife. A more detailed understanding of these topics might prove helpful to clinicians seeking guidance for how best to care for Jewish patients, to anyone supporting dying individuals, or to anyone interested in learning more about the subject. The objectives of this chapter are to examine Jewish approaches to key bioethical issues surrounding palliative care, to analyze meaning-making rituals following a loss, at a funeral, and throughout mourning, and to explore Jewish beliefs in an afterlife. Research was collected from sacred texts, legal codes, modern rabbinic responsa literature, and secondary sources. Core, guiding principles include human beings' creation "in the image of God," an obligation to save life, an obligation to mitigate pain, a prohibition against self-harm and hastening death, respect for the dead, and ritualized mourning periods ("shiva," "shloshim," and "shanah"), which feature special liturgy ("kaddish") and practices. Judaism is a religion that values thorough questioning, debate, and argumentation. It also encompasses diverse cultural and ethnic backgrounds, and various denominations. Many Jews are also unaffiliated with a movement or rarely engage with traditional law altogether. For all of these reasons, no summary can comprehensively encapsulate the wide range of opinions that exist around any given topic. That said, what follows is a detailed overview of traditional Jewish approaches to artificial nutrition/hydration, extubation, dialysis, euthanasia and more. It also outlines rituals surrounding and following death. Finally, views and beliefs of the afterlife are presented, as they often serve to imbue meaning and comfort in times of grief, uncertainty, and transition.


Asunto(s)
Judíos , Judaísmo , Humanos , Pesar
2.
Wellcome Open Res ; 4: 116, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32258425

RESUMEN

The FRAXA and FRAXE alleles of the FMR1 and FMR2 genes located on the X chromosome contain varying numbers of trinucleotide repeats. Large numbers of repeats at FRAXA (full mutations) manifest as Fragile X syndrome, associated with mental impairment that affects males more severely. In this paper, we present the dataset of frequencies of FRAXA and FRAXE repeat size extracted from DNA samples collected from boys enrolled in the Avon Longitudinal Study of Parents and Children (ALSPAC). DNA data were extracted from samples collected in ALSPAC clinics from several types of samples: cord blood, venepuncture blood taken at 43 months, 61 months, seven years or nine years. The DNA was amplified at FRAXA and FRAXE using fluorescent PCR in the Wessex Regional Genetics Laboratory, Salisbury District Hospital. The mean repeat size for FRAXA is 28.92 (S.D. 5.44), the median 30 and the range 8 to 68. There were particularly high numbers of boys with repeat sizes of 20 (10.67%) and 23 (7.35%). The mean repeat size for FRAXE is 17.41 (S.D. 3.94), with median of 16 and range of 0 to 61. There is a relatively high degree of variation of the FRAXA repeat size particularly and we suggest the extensive data available from the ALSPAC study opens up areas of research into understanding phenotypes associated with relatively unexplored repeat sizes. This could be particularly interesting for the lower repeat sizes occurring with high frequency at FRAXA in this population. As the data can be linked to exposures and phenotypes, it will provide a resource for researchers worldwide.

3.
Am J Med Genet A ; 170(10): 2671-80, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27287007

RESUMEN

Studies during the past 50 years demonstrate the importance of chromosome abnormalities to the occurrence of early pregnancy loss in humans. Intriguingly, there appears to be considerable variation in the rates of chromosome abnormality, with more recent studies typically reporting higher levels than those reported in early studies of spontaneous abortions. We were interested in examining the basis for these differences and accordingly, we reviewed studies of spontaneous abortions conducted in our laboratories over a 40-year-time span. Our analyses confirm a higher rate of abnormality in more recent series of spontaneous abortions, but indicate that the effect is largely, if not entirely, attributable to changes over time in the maternal age structures of the study populations. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Aborto Espontáneo/epidemiología , Aborto Espontáneo/genética , Aberraciones Cromosómicas , Aborto Espontáneo/historia , Conjuntos de Datos como Asunto , Femenino , Edad Gestacional , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Cariotipo , Edad Materna , Vigilancia de la Población , Embarazo , Razón de Masculinidad , Trisomía
4.
Artículo en Inglés | MEDLINE | ID: mdl-25184528

RESUMEN

This article is one person's view of human cytogenetics over the past 50 years. The flowering of human cytogenetics led the way to the establishment of clinical genetics as one of the most important developments in medicine in the twentieth century. The article is written from the viewpoint of a scientist who never tired of analyzing the images of dividing cells on the light microscope and interpreting the wealth of information contained in them.


Asunto(s)
Citodiagnóstico , Citogenética/historia , Genética Médica/historia , Microscopía , Aberraciones Cromosómicas , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Cariotipificación
5.
Nature ; 508(7494): 98-102, 2014 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-24670643

RESUMEN

Changes in gene dosage are a major driver of cancer, known to be caused by a finite, but increasingly well annotated, repertoire of mutational mechanisms. This can potentially generate correlated copy-number alterations across hundreds of linked genes, as exemplified by the 2% of childhood acute lymphoblastic leukaemia (ALL) with recurrent amplification of megabase regions of chromosome 21 (iAMP21). We used genomic, cytogenetic and transcriptional analysis, coupled with novel bioinformatic approaches, to reconstruct the evolution of iAMP21 ALL. Here we show that individuals born with the rare constitutional Robertsonian translocation between chromosomes 15 and 21, rob(15;21)(q10;q10)c, have approximately 2,700-fold increased risk of developing iAMP21 ALL compared to the general population. In such cases, amplification is initiated by a chromothripsis event involving both sister chromatids of the Robertsonian chromosome, a novel mechanism for cancer predisposition. In sporadic iAMP21, breakage-fusion-bridge cycles are typically the initiating event, often followed by chromothripsis. In both sporadic and rob(15;21)c-associated iAMP21, the final stages frequently involve duplications of the entire abnormal chromosome. The end-product is a derivative of chromosome 21 or the rob(15;21)c chromosome with gene dosage optimized for leukaemic potential, showing constrained copy-number levels over multiple linked genes. Thus, dicentric chromosomes may be an important precipitant of chromothripsis, as we show rob(15;21)c to be constitutionally dicentric and breakage-fusion-bridge cycles generate dicentric chromosomes somatically. Furthermore, our data illustrate that several cancer-specific mutational processes, applied sequentially, can coordinate to fashion copy-number profiles over large genomic scales, incrementally refining the fitness benefits of aggregated gene dosage changes.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 21/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Cromátides/genética , Rotura Cromosómica , Cromosomas Humanos Par 15/genética , Variaciones en el Número de Copia de ADN/genética , Humanos , Recombinación Genética/genética , Translocación Genética/genética
6.
Genet Med ; 16(1): 19-24, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23703681

RESUMEN

PURPOSE: Primary ovarian insufficiency before the age of 40 years affects 1% of the female population and is characterized by permanent cessation of menstruation. Genetic causes include FMR1 expansion mutations. Previous studies have estimated mutation prevalence in clinical referrals for primary ovarian insufficiency, but these are likely to be biased as compared with cases in the general population. The prevalence of FMR1 expansion mutations in early menopause (between the ages of 40 and 45 years) has not been published. METHODS: We studied FMR1 CGG repeat number in more than 2,000 women from the Breakthrough Generations Study who underwent menopause before the age of 46 years. We determined the prevalence of premutation (55-200 CGG repeats) and intermediate (45-54 CGG repeats) alleles in women with primary ovarian insufficiency (n = 254) and early menopause (n = 1,881). RESULTS: The prevalence of the premutation was 2.0% in primary ovarian insufficiency, 0.7% in early menopause, and 0.4% in controls, corresponding to odds ratios of 5.4 (95% confidence interval = 1.7-17.4; P = 0.004) for primary ovarian insufficiency and 2.0 (95% confidence interval = 0.8-5.1; P = 0.12) for early menopause. Combining primary ovarian insufficiency and early menopause gave an odds ratio of 2.4 (95% confidence interval = 1.02-5.8; P = 0.04). Intermediate alleles were not significant risk factors for either early menopause or primary ovarian insufficiency. CONCLUSION: FMR1 premutations are not as prevalent in women with ovarian insufficiency as previous estimates have suggested, but they still represent a substantial cause of primary ovarian insufficiency and early menopause.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Menopausia Prematura/genética , Insuficiencia Ovárica Primaria/genética , Adulto , Estudios de Casos y Controles , Femenino , Variación Genética , Humanos , Modelos Lineales , Modelos Logísticos , Persona de Mediana Edad , Insuficiencia Ovárica Primaria/diagnóstico , Estudios Prospectivos , Expansión de Repetición de Trinucleótido , Reino Unido
7.
J Health Serv Res Policy ; 18(4): 195-201, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23864125

RESUMEN

OBJECTIVES: Pregnant women who receive a high screening risk result for Down, Edwards or Patau syndrome are offered diagnostic tests that carry a procedure-related risk of miscarriage. This study quantifies the improvement in the screening tests by calculating the number of women who had such tests per syndrome diagnosis from 1991 to 2010. METHODS: Routinely stored data on prenatal chorionic villus sampling (CVS) and amniocentesis samples performed from 1991 to 2010 from the Wessex Regional Genetics Laboratory in England were extracted from the laboratory database. The numbers of diagnostic tests performed per Down, Edwards or Patau syndrome diagnosis were calculated according to the type of diagnostic test, and were adjusted for maternal age and gestational age at diagnosis. RESULTS: A total of 32,345 CVSs and amniocenteses identified 872 diagnoses of Down syndrome and 328 of Edwards and Patau syndrome. In 1991, there were 46 (95%CI: 16-111) CVSs per syndrome diagnosis compared with five (95%CI: 4-7) in 2010. For amniocenteses, the number fell from 53 (37-78) to 15 (11-22). CONCLUSION: This analysis demonstrates the improvements in antenatal screening for Down syndrome that have been made over the past 20 years, resulting in a reduction in the number of women tested and thus in the number of foetal deaths attributable to the testing procedure.


Asunto(s)
Síndrome de Down/diagnóstico , Diagnóstico Prenatal , Mejoramiento de la Calidad/tendencias , Adulto , Amniocentesis , Muestra de la Vellosidad Coriónica , Trastornos de los Cromosomas/diagnóstico , Trastornos de los Cromosomas/epidemiología , Cromosomas Humanos Par 13 , Bases de Datos Factuales , Síndrome de Down/epidemiología , Inglaterra/epidemiología , Femenino , Humanos , Embarazo , Trisomía/diagnóstico , Síndrome de la Trisomía 13
9.
Eur J Med Genet ; 56(1): 1-6, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23059468

RESUMEN

Integrity of the long arm of the X chromosome is important for maintaining female fertility and several critical regions for normal ovarian function have been proposed. In order to understand further the importance of specific areas of the X chromosome, we describe a series of 20 previously unreported patients missing part of Xq in whom detailed phenotypic information has been gathered as well as precise chromosome mapping using array Comparative Genomic Hybridization. Features often associated with Turner syndrome were not common in our study and excluding puberty, menarche and menstruation, the phenotypes observed were present in only a minority of women and were not specific to the X chromosome. The most frequently occurring phenotypic features in our patients were abnormalities of menstruation and fertility. Larger terminal deletions were associated with a higher incidence of primary ovarian failure, occurring at a younger age; however patients with similar or even identical deletions had discordant menstrual phenotypes, making accurate genetic counselling difficult. Nevertheless, large deletions are likely to be associated with complete skewing of X inactivation so that the resulting phenotypes are relatively benign given the amount of genetic material missing, even in cases with unbalanced X;autosome translocations. Some degree of ovarian dysfunction is highly likely, especially for terminal deletions extending proximal to Xq27. In conjunction with patient data from the literature, our study suggests that loss of Xq26-Xq28 has the most significant effect on ovarian function.


Asunto(s)
Deleción Cromosómica , Cromosomas Humanos X , Fertilidad/genética , Menstruación/genética , Aberraciones Cromosómicas , Mapeo Cromosómico , Femenino , Humanos , Menopausia/genética , Fenotipo , Pubertad/genética , Inactivación del Cromosoma X
10.
Hum Genet ; 131(9): 1519-24, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22643917

RESUMEN

Recent studies have identified PRDM9, a zinc finger (ZF) protein, as a key regulator of meiotic recombination. As both recurrent genomic disorders and chromosomal non-disjunction are known to be associated with specific unusual patterns of recombination, we hypothesized a possible link between PRDM9 ZF variation and susceptibility to microdeletion syndromes and/or trisomy. We sequenced the PRDM9 ZF domain in 271 parents of patients with de novo microdeletions of known parental origin (velocardiofacial syndrome, the 17q21.31 microdeletion syndrome, Prader-Willi/Angelman syndrome and Williams-Beuren syndrome), and in 61 parents of individuals with a supernumerary X chromosome. We compared PRDM9 ZF genotype frequencies between parents in whose germ line the de novo rearrangement occurred and their spouses. We observed a significantly increased frequency (p = 0.006) of PRDM9 variants in parents who transmitted de novo 7q11.23 deletions to their offspring. These data suggest that certain PRDM9 alleles may be associated with an increased susceptibility to recurrent 7q11.23 microdeletions that cause Williams-Beuren syndrome. However, as the majority of parents who transmitted a de novo microdeletion/supernumerary X chromosome to their offspring have the common AA genotype, we conclude that none of the rearrangements we have studied are dependent on specific non-A PRDM9 alleles.


Asunto(s)
Enfermedades Genéticas Congénitas/genética , Predisposición Genética a la Enfermedad , Variación Genética , Genómica , No Disyunción Genética , Humanos
11.
Am J Med Genet A ; 158A(5): 1151-7, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22438132

RESUMEN

This study describes the characteristics of karyotypes leading to phenotypic Down syndrome (trisomy 21) in 29,256 cases diagnosed between 1989 and 2009 in England and Wales included in the National Down Syndrome Cytogenetic Register (NDSCR). The frequency of occurrence of the different karyotypes, proportions diagnosed prenatally, sex ratios, mean maternal age, and proportions of mothers with recurrences were analyzed. Nearly 97% of all cases were free trisomy 21; 2.9% contributory trisomy 21, 0.3% double or triple aneuploidies; 1% of all were mosaics. Mean maternal age of free trisomy 21 cases was 35 years, 54% were male, and 1% of mothers had recurrences. Free trisomy 21 mosaics had a lower mean maternal age (33 years), a lower proportion of males (39.5%), and 2.5% of mothers had recurrences. The majority of contributory translocations were Robertsonian or rea (21;21). Their mothers were younger, particularly those of Robertsonian translocations (28 years). Of the Robertsonian der (14;21) translocations of known parental origin, 54% were de novo, 41% maternal and 5% paternal and 15.8% of mothers of those of maternal origin had recurrences. Multiple aneuploidies have the highest proportion of males (67%), highest proportion of mosaics (40%), a mean maternal age of 37 years, and no mothers had a recurrence. The size of this national register allowed the frequency of occurrence of the rarer karyotypes of Down syndrome to be estimated and their epidemiology described.


Asunto(s)
Síndrome de Down/epidemiología , Síndrome de Down/genética , Adulto , Citogenética , Inglaterra/epidemiología , Femenino , Humanos , Cariotipo , Masculino , Mosaicismo , Prohibitinas , Sistema de Registros , Gales/epidemiología
12.
Eur J Hum Genet ; 20(2): 155-60, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21952720

RESUMEN

We report a large series of 173 patients with physical and/or neurological abnormalities and a de novo imbalance identified by array CGH. Breakpoint intervals were screened for the presence of low copy repeats (LCRs) to distinguish between rearrangements formed by non-allelic homologous recombination (NAHR) and rearrangements formed by other mechanisms. We identified significant differences in size and parental origin between the LCR-mediated and non-LCR groups. Non-LCR imbalances were evenly distributed among the four size intervals we defined, whereas LCR-mediated rearrangements had a narrow size distribution, predominantly between 1 and 5 Mb (P = 0.001). Among the LCR-mediated rearrangements there were equal numbers of maternally and paternally derived cases. In contrast, for the non-LCR rearrangements there was a significant excess of paternal cases (P = 0.024) over a wide size range including below 1 Mb. Our results provide novel evidence that unbalanced chromosome rearrangements are not only more frequent in males, but may also arise through different mechanisms than those seen in females. Although the paternal imbalances identified in our study are evenly distributed throughout the four size groups, there are very few maternal imbalances either <1 Mb or >10 Mb. Furthermore, a lower proportion of paternal imbalances are LCR mediated (13/71) compared with the maternal imbalances (12/30). We hypothesise that imbalances of maternal origin arise predominantly through NAHR during meiosis, while the majority of imbalances of paternal origin arise through male-specific mechanisms other than NAHR. Our data suggest that mitotic mechanisms could be important for the formation of chromosome imbalances; however, we found no association with increased paternal age.


Asunto(s)
Desequilibrio Alélico , Duplicación de Gen , Eliminación de Secuencia , Factores de Edad , Hibridación Genómica Comparativa , Femenino , Humanos , Masculino , Duplicaciones Segmentarias en el Genoma , Translocación Genética
13.
Nat Rev Genet ; 12(6): 384, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21577227

RESUMEN

The 2011 March of Dimes Prize in Developmental Biology has been jointly awarded to Patricia Jacobs, of Southampton University Medical School and the Wessex Regional Genetics Laboratory, and to David Page, of the Whitehead Institute, Massachusetts Institute of Technology and Howard Hughes Medical Institute, for their pioneering research on the X and Y chromosomes. The prize recognizes researchers whose work has contributed to our understanding of the science that underlies birth defects. We talked to the winners about their achievements and the impact these have had on human health. This month's interview is with Patricia Jacobs, who spoke to Louisa Flintoft. The interview with David Page will appear in our July issue.


Asunto(s)
Genética/historia , Aberraciones Cromosómicas , Femenino , Historia del Siglo XX , Humanos , Síndrome de Klinefelter/genética , Masculino , Reino Unido
14.
Hum Mol Genet ; 20(1): 186-92, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-20952801

RESUMEN

Women become infertile approximately 10 years before menopause, and as more women delay childbirth into their 30s, the number of women who experience infertility is likely to increase. Tests that predict the timing of menopause would allow women to make informed reproductive decisions. Current predictors are only effective just prior to menopause, and there are no long-range indicators. Age at menopause and early menopause (EM) are highly heritable, suggesting a genetic aetiology. Recent genome-wide scans have identified four loci associated with variation in the age of normal menopause (40-60 years). We aimed to determine whether theses loci are also risk factors for EM. We tested the four menopause-associated genetic variants in a cohort of approximately 2000 women with menopause≤45 years from the Breakthrough Generations Study (BGS). All four variants significantly increased the odds of having EM. Comparing the 4.5% of individuals with the lowest number of risk alleles (two or three) with the 3.0% with the highest number (eight risk alleles), the odds ratio was 4.1 (95% CI 2.4-7.1, P=4.0×10(-7)). In combination, the four variants discriminated EM cases with a receiver operator characteristic area under the curve of 0.6. Four common genetic variants identified by genome-wide association studies, had a significant impact on the odds of having EM in an independent cohort from the BGS. The discriminative power is still limited, but as more variants are discovered they may be useful for predicting reproductive lifespan.


Asunto(s)
Estudio de Asociación del Genoma Completo , Menopausia Prematura/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Factores de Edad , Alelos , Proteínas de Ciclo Celular/genética , Femenino , Humanos , Persona de Mediana Edad , Proteínas de Mantenimiento de Minicromosoma , Reproducción , Factores de Riesgo
15.
Arch Dis Child ; 96(10): 954-9, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20656736

RESUMEN

PURPOSE: Sex chromosome trisomies (SCTs) are found on amniocentesis in 2.3-3.7 per 1000 same-sex births, yet there is a limited database on which to base a prognosis. Autism has been described in postnatally diagnosed cases of Klinefelter syndrome (XXY karyotype), but the prevalence in non-referred samples, and in other trisomies, is unclear. The authors recruited the largest sample including all three SCTs to be reported to date, including children identified on prenatal screening, to clarify this issue. DESIGN: Parents of children with a SCT were recruited either via prenatal screening or via a parental support group, to give a sample of 58 XXX, 19 XXY and 58 XYY cases. Parents were interviewed using the Vineland Adaptive Behavior Scales and completed questionnaires about the communicative development of children with SCTs and their siblings (42 brothers and 26 sisters). RESULTS: Rates of language and communication problems were high in all three trisomies. Diagnoses of autism spectrum disorder (ASD) were found in 2/19 cases of XXY (11%) and 11/58 XYY (19%). After excluding those with an ASD diagnosis, communicative profiles indicative of mild autistic features were common, although there was wide individual variation. CONCLUSIONS: Autistic features have not previously been remarked upon in studies of non-referred samples with SCTs, yet the rate is substantially above population levels in this sample, even when attention is restricted to early-identified cases. The authors hypothesise that X-linked and Y-linked neuroligins may play a significant role in the aetiology of communication impairments and ASD.


Asunto(s)
Trastornos Generalizados del Desarrollo Infantil/genética , Trastornos del Desarrollo del Lenguaje/genética , Aberraciones Cromosómicas Sexuales , Trisomía , Niño , Trastornos Generalizados del Desarrollo Infantil/psicología , Educación Especial , Escolaridad , Femenino , Humanos , Cariotipificación , Trastornos del Desarrollo del Lenguaje/terapia , Terapia del Lenguaje , Masculino , Diagnóstico Prenatal/métodos , Psicometría , Logopedia
16.
Hum Reprod ; 25(5): 1335-8, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20228389

RESUMEN

BACKGROUND: It is recognized that FMR1 premutation expansions are associated with premature ovarian failure (POF), but the role of smaller repeats at the boundary of premutation and normal is less clear. METHODS: We have therefore investigated the incidence of these intermediate sized FMR1 CGG repeats (35-58 repeats) in a series of 366 women ascertained because of menopause before the age of 40. RESULTS: We found no significant difference in the incidence of intermediates in cases compared with controls. Thus, we were unable to replicate previous studies showing a positive association, despite a significantly larger sample size. CONCLUSIONS: We therefore conclude that intermediate sized FMR1 CGG repeat alleles should not be considered a high-risk factor for POF based on current evidence.


Asunto(s)
Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Insuficiencia Ovárica Primaria/etiología , Insuficiencia Ovárica Primaria/genética , Expansión de Repetición de Trinucleótido , Adolescente , Adulto , Alelos , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Femenino , Humanos , Mutación , Adulto Joven
17.
Dev Med Child Neurol ; 52(2): 119-29, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20059514

RESUMEN

AIM: To review systematically the neurodevelopmental characteristics of individuals with sex chromosome trisomies (SCTs). METHOD: A bibliographic search identified English-language articles on SCTs. The focus was on studies unbiased by clinical referral, with power of at least 0.69 to detect an effect size of 1.0. RESULTS: We identified 35 articles on five neonatally identified samples that had adequate power for our review. An additional 11 studies were included where cases had been identified for reasons other than neurodevelopmental concerns. Individuals with an additional X chromosome had mean IQs that were within broadly normal limits but lower than the respective comparison groups, with verbal IQ most affected. Cognitive outcomes were poorest for females with XXX. Males with XYY had normal-range IQs, but all three SCT groups (XXX, XXY, and XYY) had marked difficulties in speech and language, motor skills, and educational achievement. Nevertheless, most adults with SCTs lived independently. Less evidence was available for brain structure and for attention, social, and psychiatric outcomes. Within each group there was much variation. INTERPRETATION: Individuals with SCTs are at risk of cognitive and behavioural difficulties. However, the evidence base is slender, and further research is needed to ascertain the nature, severity, and causes of these difficulties in unselected samples.


Asunto(s)
Trastornos de los Cromosomas/genética , Trastornos de los Cromosomas/patología , Discapacidad Intelectual/genética , Cromosomas Sexuales/genética , Trisomía , Niño , Bases de Datos Factuales/estadística & datos numéricos , Discapacidades del Desarrollo/genética , Femenino , Humanos , Cariotipificación , Masculino , Pruebas Neuropsicológicas
18.
J Med Genet ; 47(2): 112-5, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19638350

RESUMEN

BACKGROUND: Congenital chromosome abnormalities are relatively common in our species and among structural abnormalities the most common class is balanced reciprocal translocations. Determining the parental origin of de novo balanced translocations may provide insights into how and when they arise. While there is a general paternal bias in the origin of non-recurrent unbalanced rearrangements, there are few data on parental origin of non-recurrent balanced rearrangements. METHODS: The parental origin of a series of de novo balanced reciprocal translocations was determined using DNA from flow sorted derivative chromosomes and linkage analysis. RESULTS: Of 27 translocations, we found 26 to be of paternal origin and only one of maternal origin. We also found the paternally derived translocations to be associated with a significantly increased paternal age (p<0.008). CONCLUSION: Our results suggest there is a very pronounced paternal bias in the origin of all non-recurrent reciprocal translocations and that they may arise during one of the numerous mitotic divisions that occur in the spermatogonial germ cells prior to meiosis.


Asunto(s)
Puntos de Rotura del Cromosoma , Edad Paterna , Análisis de Secuencia de ADN/métodos , Translocación Genética , Adulto , Femenino , Ligamiento Genético , Humanos , Masculino , Persona de Mediana Edad , Fenotipo
19.
Hum Genet ; 125(2): 181-8, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19104840

RESUMEN

The majority of constitutional reciprocal translocations appear to be unique rearrangements arising from independent events. However, a small number of translocations are recurrent, most significantly the t(11;22)(q23;q11). Among large series of translocations there may be multiple independently ascertained cases with the same cytogenetic breakpoints. Some of these could represent additional recurrent rearrangements, alternatively they could be identical by descent (IBD) or have subtly different breakpoints when examined under higher resolution. We have used molecular breakpoint mapping and haplotyping to determine the origin of three pairs of reciprocal constitutional translocations, each with the same cytogenetic breakpoints. FISH mapping showed one pair to have different breakpoints and thus to be distinct rearrangements. Another pair of translocations were IBD with identical breakpoint intervals and highly conserved haplotypes on the derived chromosomes. The third pair, t(4;11)(p16.2;p15.4), had the same breakpoint intervals by aCGH and fosmid mapping but had very different haplotypes, therefore they represent a novel recurrent translocation. Unlike the t(11;22)(q23;q11), the formation of the t(4;11)(p16.2;p15.4) may have involved segmental duplications and sequence homology at the breakpoints. Additional examples of recurrent translocations could be identified if the resources were available to study more translocations using the approaches described here. However, like the t(4;11)(p16.2;p15.4), such translocations are likely to be rare with the t(11;22) remaining the only common recurrent constitutional reciprocal translocation.


Asunto(s)
Mapeo Cromosómico/métodos , Cromosomas Humanos/genética , Haplotipos/genética , Translocación Genética/genética , Humanos , Hibridación Fluorescente in Situ , Repeticiones de Microsatélite/genética , Análisis de Secuencia por Matrices de Oligonucleótidos
20.
J Clin Endocrinol Metab ; 93(12): 4735-42, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18812477

RESUMEN

CONTEXT: Turner syndrome is characterized by complete or partial X chromosome monosomy. It is associated with substantial morbidity, but mortality risks and causes of death are not well described. OBJECTIVES: Our objective was to investigate mortality and causes of death in women with Turner syndrome. DESIGN AND SETTING: We constructed a cohort of women diagnosed with Turner syndrome at almost all cytogenetic centers in Great Britain and followed them for mortality. PATIENTS: A total of 3,439 women diagnosed between 1959-2002 were followed to the end of 2006. OUTCOME MEASURES: Standardized mortality ratios (SMRs) and absolute excess risks were evaluated. RESULTS: In total, 296 deaths occurred. Mortality was significantly raised overall [SMR = 3.0; 95% confidence interval (CI) = 2.7-3.4] and was raised for nearly all major causes of death. Circulatory disease accounted for 41% of excess mortality, with greatest SMRs for aortic aneurysm (SMR = 23.6; 95% CI = 13.8-37.8) and aortic valve disease (SMR = 17.9; 95% CI = 4.9-46.0), but SMRs were also raised for other circulatory conditions. Other major contributors to raised mortality included congenital cardiac anomalies, diabetes, epilepsy, liver disease, noninfectious enteritis and colitis, renal and ureteric disease, and pneumonia. Absolute excess risks of death were considerably greater at older than younger ages. CONCLUSIONS: Mortality in women with Turner syndrome is 3-fold higher than in the general population, is raised for almost all major causes of death, and is raised at all ages, with the greatest excess mortality in older adulthood. These risks need consideration in follow-up and counseling of patients and add to reasons for continued follow-up and preventive measures in adult, not just pediatric, care.


Asunto(s)
Síndrome de Turner/mortalidad , Mujeres , Adolescente , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/complicaciones , Aneurisma de la Aorta/mortalidad , Insuficiencia de la Válvula Aórtica/complicaciones , Insuficiencia de la Válvula Aórtica/mortalidad , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Causas de Muerte , Estudios de Cohortes , Intervalos de Confianza , Análisis Citogenético , Femenino , Humanos , Cariotipificación , Persona de Mediana Edad , Neoplasias/complicaciones , Neoplasias/epidemiología , Estudios Retrospectivos , Riesgo , Reino Unido/epidemiología , Adulto Joven
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