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Joan K Morris - One of the best experts on this subject based on the ideXlab platform.
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Trisomy 21 Mosaicism and maternal age
American Journal of Medical Genetics Part A, 2012Co-Authors: Joan K MorrisAbstract:The aim of this study was to quantify the maternal age-specific risk for trisomy 21 Mosaicism. Data were obtained on 322 trisomy 21 diagnoses with Mosaicism and 27,943 simple trisomy 21 diagnoses recorded in the National Down Syndrome Cytogenetic Register from 1989 to 2009 in England and Wales. Trisomy 21 cases with Mosaicism have a mean maternal age of 33.1 years compared to 35.0 years for free trisomy 21 cases. Sixty-seven percent of trisomy 21 diagnoses with Mosaicism are maternal age dependent, with a risk 0.8% that of the corresponding maternal age specific risk for simple trisomy 21. However 33% (0.8 per 100,000 births) are not maternal age dependent, indicating that maternal age is not the only risk factor for Mosaicism. Trisomy 21 diagnoses with Mosaicism are more likely to be female than free trisomy 21 diagnoses, however there was no association of fetal sex with maternal age which indicates that there is another factor involved in the presence of Mosaicism not associated with maternal age, but associated with fetal sex. © 2012 Wiley Periodicals, Inc.
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Trisomy 21 Mosaicism and maternal age.
American journal of medical genetics. Part A, 2012Co-Authors: Joan K MorrisAbstract:The aim of this study was to quantify the maternal age-specific risk for trisomy 21 Mosaicism. Data were obtained on 322 trisomy 21 diagnoses with Mosaicism and 27,943 simple trisomy 21 diagnoses recorded in the National Down Syndrome Cytogenetic Register from 1989 to 2009 in England and Wales. Trisomy 21 cases with Mosaicism have a mean maternal age of 33.1 years compared to 35.0 years for free trisomy 21 cases. Sixty-seven percent of trisomy 21 diagnoses with Mosaicism are maternal age dependent, with a risk 0.8% that of the corresponding maternal age specific risk for simple trisomy 21. However 33% (0.8 per 100,000 births) are not maternal age dependent, indicating that maternal age is not the only risk factor for Mosaicism. Trisomy 21 diagnoses with Mosaicism are more likely to be female than free trisomy 21 diagnoses, however there was no association of fetal sex with maternal age which indicates that there is another factor involved in the presence of Mosaicism not associated with maternal age, but associated with fetal sex.
Deepa Bhartiya - One of the best experts on this subject based on the ideXlab platform.
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Y chromosome Mosaicism and occurrence of gonadoblastoma in cases of Turner syndrome and amenorrhoea.
Reproductive BioMedicine Online, 2007Co-Authors: Deepak Modi, Deepa BhartiyaAbstract:In the present study, 73 cases with a clinical diagnosis of Turner syndrome, or with primary or secondary amenorrhoea without frank Turner phenotype, were evaluated for presence of low level Y chromosome Mosaicism using molecular methods. Fluorescence in-situ hybridization for centromere and q arm of the Y chromosome and nested polymerase chain reaction for the sex determining region on Y (SRY) gene were performed in peripheral blood, buccal cells and gonadal biopsies. The overall frequency of Y chromosome Mosaicism was found to be 18% (13/73 cases). Four cases (16%) of Turner syndrome had Y chromosome Mosaicism, seven cases (28%) with primary amenorrhoea and two cases (9%) with secondary amenorrhoea had Y chromosome Mosaicism. Histologically detectable gonadoblastoma was observed in one of seven cases (14%) that had Y chromosome Mosaicism. This frequency is lower than that reported previously, underscoring the need for large prospective investigations to determine the frequency of Y chromosome Mosaicism and occurrence of gonadoblastoma in cases of Turner syndrome and other forms of amenorrhoea.
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Down syndrome: a study of chromosomal Mosaicism.
Reproductive BioMedicine Online, 2003Co-Authors: Deepak Modi, Prajakta Berde, Deepa BhartiyaAbstract:Abstract Recent data suggest that chromosome Mosaicism is a possible mechanism for intrauterine and postnatal survival in cases of trisomy 18 and Turner syndrome (45X). The aim of this study was to evaluate if chromosomal Mosaicism is a possible mechanism of survival in Down syndrome (DS) (trisomy 21) individuals. Mosaicism was studied by interphase fluorescence in-situ hybridization (FISH), using a specific probe for chromosome 21 (21q22.13–21q22.2) in 78 cases suspected of DS. To rule out tissue specific Mosaicism, buccal cells or amniocytes were analysed in addition to blood in 20 DS cases. Thirty-three per cent of the cases studied by FISH in only peripheral blood were mosaics. In 20 cases of trisomy 21, two tissues were studied and Mosaicism was not detected in either of the two tissues in 15 cases. The remaining five cases were mosaics in both the tissues analysed. Clinical comparisons in 17 DS mosaics showed a direct relationship between the percentage of trisomic cells and the degree of phenotypic manifestations. These results suggest that mechanism(s) other than Mosaicism may exist for the intrauterine and postnatal survival of DS cases.
Paulie Papavassiliou - One of the best experts on this subject based on the ideXlab platform.
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Mosaicism for trisomy 21 a review
American Journal of Medical Genetics Part A, 2015Co-Authors: Paulie Papavassiliou, Chariyawan Charalsawadi, Kelly Rafferty, Colleen JacksoncookAbstract:The clinical and cytogenetic findings associated with Mosaicism for trisomy 21/Down syndrome are the focus of this review. The primary topics discussed in this overview of the extant literature include the history of this condition and its diagnosis, the incidence of Mosaicism, the meiotic and/or mitotic chromosomal malsegregation events resulting in Mosaicism, the observation of Mosaicism in the parents of children with the non-mosaic form of Down syndrome, and the variation in phenotypic outcome for both constitutional and acquired traits present in people with Mosaicism for trisomy 21/Down syndrome, including cognition, fertility, and overall phenotypic findings. Additional topics reviewed include the social conditions of people with Mosaicism, as well as age-related and epigenetic alterations observed in people with Mosaicism for trisomy 21/Down syndrome. © 2014 Wiley Periodicals, Inc.
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Mosaicism for trisomy 21: a review.
American journal of medical genetics. Part A, 2014Co-Authors: Paulie Papavassiliou, Chariyawan Charalsawadi, Kelly Rafferty, Colleen Jackson-cookAbstract:The clinical and cytogenetic findings associated with Mosaicism for trisomy 21/Down syndrome are the focus of this review. The primary topics discussed in this overview of the extant literature include the history of this condition and its diagnosis, the incidence of Mosaicism, the meiotic and/or mitotic chromosomal malsegregation events resulting in Mosaicism, the observation of Mosaicism in the parents of children with the non-mosaic form of Down syndrome, and the variation in phenotypic outcome for both constitutional and acquired traits present in people with Mosaicism for trisomy 21/Down syndrome, including cognition, fertility, and overall phenotypic findings. Additional topics reviewed include the social conditions of people with Mosaicism, as well as age-related and epigenetic alterations observed in people with Mosaicism for trisomy 21/Down syndrome. .
D. G. M. Lewis - One of the best experts on this subject based on the ideXlab platform.
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Mosaicism and the trisomy 8 syndrome.
Clinical genetics, 2008Co-Authors: A. C. Berry, D. E. Mutton, D. G. M. LewisAbstract:Three new cases of trisomy 8 Mosaicism are presented; two have features corresponding with those usually found in this syndrome, whereas one is highly atypical. In view of the almost universal Mosaicism of these patients, the literature is reviewed with an emphasis on the patterns of Mosaicism found. There is little correlation between degree of Mosaicism and extent of clinical abnormality. The degree of Mosaicism differs in different tissues, fibroblasts being more informative of aneuploidy than lymphocytes, and there is some evidence that the degree of Mosaicism varies with time. The reasons for these findings are discussed, with particular reference to the raised paternal age found in a proportion of the reported cases.
Colleen Jackson-cook - One of the best experts on this subject based on the ideXlab platform.
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Mosaicism for trisomy 21: a review.
American journal of medical genetics. Part A, 2014Co-Authors: Paulie Papavassiliou, Chariyawan Charalsawadi, Kelly Rafferty, Colleen Jackson-cookAbstract:The clinical and cytogenetic findings associated with Mosaicism for trisomy 21/Down syndrome are the focus of this review. The primary topics discussed in this overview of the extant literature include the history of this condition and its diagnosis, the incidence of Mosaicism, the meiotic and/or mitotic chromosomal malsegregation events resulting in Mosaicism, the observation of Mosaicism in the parents of children with the non-mosaic form of Down syndrome, and the variation in phenotypic outcome for both constitutional and acquired traits present in people with Mosaicism for trisomy 21/Down syndrome, including cognition, fertility, and overall phenotypic findings. Additional topics reviewed include the social conditions of people with Mosaicism, as well as age-related and epigenetic alterations observed in people with Mosaicism for trisomy 21/Down syndrome. .
