Clinical analysis of monochorionic-diamniotic twins with genetic discordance / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic etiology of 5 cases of monochorionic-diamniotic (MCDA) with genetic discordance.@*METHODS@#148 cases of MCDA twins who were diagnosed by amniocentesis at the Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region from January 2016 to June 2020 were selected as the study subjects. Relevant clinical data of the pregnant women were collected, and amniotic fluid samples of the twins were collected separately. Chromosomal karyotyping analysis and single nucleotide polymorphism array (SNP array) assay were carried out.@*RESULTS@#The results of chromosomal karyotyping analysis showed that 5 of the MCDA twins had inconsistent chromosome karyotypes, with an incidence of 3.4% (5/148). SNP array assay showed that 3 fetuses were mosaics.@*CONCLUSION@#Genetic discordance occurs among MCDA twins, and prenatal counseling for such cases should be given by doctors with experience in medical genetics and fetal medicine, and personalized clinical management should be recommended.

Gene-lifestyle interaction on coronary heart disease in adult twins of China / 中华流行病学杂志

Objective: To explore the gene-lifestyle interaction on coronary heart disease (CHD) in adult twins of China. Methods: Participants were selected from twin pairs registered in the Chinese National Twin Registry (CNTR). Univariate interaction model was used to estimate the interaction, via exploring the moderation effect of lifestyle on the genetic variance of CHD. Results: A total of 20 477 same-sex twin pairs aged ≥25 years were recruited, including 395 CHD cases, and 66 twin pairs both had CHD. After adjustment for age and sex, no moderation effects of lifestyles, including current smoking, current drinking, physical activity, intake of vegetable and fruit, on the genetic variance of CHD were found (P>0.05), suggesting no significant interactions. Conclusion: There was no evidence suggesting statistically significant gene-lifestyle interaction on CHD in adult twins of China.

Renegar del agujero en el caldero: defensas inconsistentes sobre el experimento de gemelos de Neubauer / To deny the hole in the cauldron Inconsistent defenses over Neubauer's twin experiment

El documental Three Identical Strangers, de Tim Waldle (2018) revela una investigación secreta sobre el desarrollo de hermanos genéticamente idénticos separados de manera deliberada para ser criados en circunstancias diferentes. Desde su estreno el experimento expuesto ha provocado una serie de rechazos en la opinión pública y entre los profesionales de la salud mental. El presente trabajo analiza los argumentos de los psiquiatras y psicoanalistas Leon Hoffman y Lois Oppenheim, que han cuestionado el documental y defendido el experimento, para analizar sus argumentos y evaluar si los mismos son consistentes o, por el contrario, pretenden legitimar una investigación éticamente inaceptable

Tim Waldle documentary film Three Identical Strangers (2018), reveals a secret investigation on the development of genetically identical siblings who were separated on purpose so as to be raised in different social contexts. Since it´s premiere, the exposed experiment has caused a series of rejections among public opinion and mental health professionals. This paper focuses in the arguments of psychiatrists Leon Hoffman and Lois Oppenheim in defense of the experiment and against the film, so as to analyzse if their arguments are consistent, or on the contrary, they pretend to legitimate an ethically unacceptable investigation.

Characterization of a pair of twins as blood group chimeras / 中华医学遗传学杂志

OBJECTIVE@#To delineate the blood group for a pair of twins with inconclusive ABO blood typing result.@*METHODS@#Serological test for blood group was carried out by using ABO and Rh Blood Grouping Cards (Microcolumn Gel Immunoassay). Sequence specific primer-PCR (PCR-SSP), direct sequencing and TA clone sequencing were used to analyze the ABO gene. Genetic status was analyzed by using 16 short tandem repeat (STR) markers.@*RESULTS@#Red blood cells of the twins displayed 2+ mixed agglutination phenomenon with anti-A, anti-A1 and anti-E. PCR-SSP and DNA sequencing of exons 6 to 7 revealed that they have an ABO*O.01.01/ABO*O.01.02 genotype. DNA sequencing of microsatellite enhancer region revealed presence of A gene. STR analysis revealed more than two haplotypes for 9 loci between the twins. After clustered by anti-A, the red blood cells were divided into two groups: A, CcDEe and O, CcDee, respectively.@*CONCLUSION@#Serological and molecular techniques have characterized the twins as blood group chimeras.

Research progress on genetic effects of the asymmetry of human brain structure revealed by magnetic resonance imaging / 生物医学工程学杂志

Hemispheric asymmetry is a fundamental organizing principle of the human brain. Answering the genetic effects of the asymmetry is a prerequisite for elucidating developmental mechanisms of brain asymmetries. Multi-modal magnetic resonance imaging (MRI) has provided an important tool for comprehensively interpreting human brain asymmetry and its genetic mechanism. By combining MRI data, individual differences in brain structural asymmetry have been investigated with quantitative genetic brain mapping using gene-heritability. Twins provide a useful natural model for studying the effects of genetics and environment on the brain. Studies based on MRI have found that the asymmetry of human brain structure has a genetic basis. From the perspective of quantitative genetic analysis, this article reviews recent findings on the genetic effects of asymmetry and genetic covariance between hemispheres from three aspects: the asymmetry of heritability, the heritability of asymmetry and the genetic correlation. At last, the article shows the limitations and future research directions in this field. The purpose of this systematic review is to quickly guide researchers to understand the origins and genetic mechanism of interhemispheric differences, and provide a genetic basis for further understanding and exploring individual differences in laterized cognitive behavior.

Rh Blood Grouping of the Individuals Born of Rh Negative Mother and Rh Positive Biological Father.

Unlike ABO antigens, Rh antigens are present only on Red Blood Cells (RBC), RhO(D) antigen is clinically the most important in the Rh system because it is highly antigenic. In India, as reported, 95% population is Rh positive whereas 05% is Rh Negative(approximately). Rh antibodies are the major cause3 of haemolytic disease of newborn (HDN) and lead to destruction of transfused Rh Positive red cells. A total number of 799 pregnant mothers having RhD Negative Blood Group (and also their husband possessing RhD Positive Blood Group) were surveyed. Out of the 799 babies born, 662 possessed RhD Positive and 137 possessed RhD Negative Blood Group. Besides this, twin babies born of RhD Negative mother and RhD Positive Biological Father were computed separately (Total No.of such mothers being 12). In case of twin delivery, the twins babies all possessed RhD Positive Blood Group. Calculation shows that about 17% of babies were RhD Negative and 83% were RhD Positive.

Efeitos genéticos e ambientais sobre os fenótips da aptidão física relacionadaa à saúde: um estudo com gêmeos / Geetic and envirronmental effects on physical fitnss phenotypes rrelated to health: a study with twins

Este estudo teve como objetivo estimar os efeitos genéticos e ambientais nos fenótipos de variáveis da aptidão física relacionada à saúde. A amostra foi composta de 52 pares de gêmeos (24 monozigóticos (MZ) e 28 dizigóticos (DZ)), com idades de 7 a 17 anos. Os testes/ medidas realizados foram: zigotia (dermatóglifos; questionário); antropometria (massa corporal; estatura); aptidão física (abdominal modificado; flexão em suspensão na barra modificada; sentar-e-alcançar modificado e vai-e-vem de 20 metros). Inicialmente, realizou-se o cálculo do coeficiente de correlação intraclasse (CCI) para os MZ e DZ em cada fenótipo (força/ resistência abdominal; superior de tronco; flexibilidade, capacidade aeróbia e IMC). Posteriormente, foram calculados os efeitos genéticos (h2), do envolvimento comum (c2) e do envolvimento único (e2), por meio de equações específicas. Os resultados revelaram predominância moderada de h2 na força/ resistência abdominal (44,8%); na flexibilidade (48%); na capacidade aeróbia (48%) e no IMC (48%); e elevada na força/ resistência superior de tronco (72%).

The purpose of this study was to estimate the genetic and environmental effects in the health-related physical fitness phenotypes. The sample of this study was constituted by 52 pairs of twins, 24 monozygotic (MZ) and 28 dizygotic (DZ) twins with ages between 7 and 17 years old. The tests/measurements carried out were: zygosity (dermatoglyphics; questionnaire); anthropometry (body mass; height); physical fitness (modified curl up; modified pull-up; modified sit and reach and 20-meter shuttle run). Initially, the intraclass correlation coefficient (ICC) was calculated for MZ and DZ in everyone phenotype (abdominal power/endurance; upper trunk power/endurance; flexibility, aerobic capacity and BMI). Then, the genetic (h2), the common environmental (c2) and the unique environmental (e2) effects were calculated, by means of specific equations. The results presented moderate predominance of h2 in the abdominal power/endurance (44.8%); flexibility (48%); aerobic capacity (48%) and BMI (48%); with strong predominance in the upper trunk power/endurance (72%).

Sirenomelia en neonato gemelo: reporte de un caso y revisión de la literatura / Sirenomelia in a newborn twin: a case report and review

La sirenomelia es una malformación congénita extremadamente rara que se caracteriza por la fusión de ambos miembros inferiores en diversos grados y se presenta un caso por cada 60,000 recién nacidos. Las primeras descripciones médicas y científicas de esta malformación datan desde el renacimiento por autores como Rochéus (1542), Palfun (1553), y Ambroise Paré (1573).

Síndrome de Russell-Silver, reporte de un caso / Russell-Silver syndrome, a case report

El síndrome de Russell-Silver fue descrito por primera vez por Russell en 1953 y confirmado por Silveren 1964 es un trastorno raro de aparente origen genético, habiéndose encontrado muchas alteraciones cromosómicas, entre ellas mutaciones a nivel del cromosoma 7 y del gen H19 y otros genes asociados al crecimiento, pero ninguna de ellas especifica de esta entidad.

O diagnóstico da zigosidade de indivíduos gêmeos para pesquisa na genética dentofacial / The diagnosis of zygosity in twins for dentofacial genetic research

O método de estudo em gêmeos está baseado na comparação dos traços apresentados pelos gêmeos monozigóticos e dizigóticos. No passado, a classificação da zigosidade era feita pela aparência facial, por um exame físico com poucos critérios, ou, ainda, pelo envio de questionários aos pais, sendo subjetivos para a pesquisa científica. Os métodos mais fidedignos, como os testes sorológicos, impressões digitais, teste sensitivo para a feniltiocarbamida, análise da placenta ao nascimento e da morfologia dental atingem uma probabilidade de acerto de no máximo 90%. O objetivo deste artigo é demonstrar a técnica de diagnóstico da zigosidade pelo teste de tipagem do DNA em pacientes odontológicos, que se caracteriza por um procedimento simples, não invasivo e de probabilidade de acerto ao redor de 99,9%. Desta forma, tomam-se questionáveis os valores de herdabilidade obtidos em estudos anteriores, onde a zigosidade era definida, muitas vezes, pela semelhança física.

Stages in the evolution of the Hardy-Weinberg law

The Hardy-Weinberg law has been used widely for about one hundred years with little question as to the foundations laid down by its originators. The basic assumption of random mating, that is choice of mates by a process akin to that of a lottery, was shown to produce genotypic proportions following the "binomial-square" rule, the so-called Hardy-Weinberg proportions (HWP). It has been assumed by many that random mating was the only way of pairing genes capable of producing HWP. However it has been shown that HWP can be obtained and maintained by non-random mating. The steps along the way to this revelation and some implications are reviewed.

Análise da morfologia oclusal dos primeiros molares permanentes em gêmeos / Analysis occlusal morphology of first molars in twins

Os dentes podem ser utilizados como amostras para o estudo da natureza e do momento da ocorrência dos distúrbios que acontecem no início da vida até após a adolescência. O arranjo bilateral dos dentes possibilitam comparaçöes do tamanho e da morfologia, nos lados direito e esquerdo, promovendo interessantes questöes sobre simetria e assimetria morfológica. A análise da morfologia oclusal dos primeiros molares permanentes, considerando a concordância assimétrica, em uma amostra de 36 pares de gêmeos monozigóticos e dizigóticos, mostrou resultados de concordância de 83 por cento a 92 por cento, principalmente em gêmeos monozogóticos

Efeitos genéticos e do envolvimento dos níveis de actividade física e aptidão física associada à saúde: um estudo em gémeos dos 6 aos 12 anos de idade do Arquipélago dos Açores (Portugal) / Genetic and environmental effects in physical activity and health related physical fitness. A study in twins aged 6-to-12 years of the Azores Islands (Portugal)

Este trabalho pretende estimar a importância de factores genéticos e do envolvimento nos níveis de actividade física (ActF) e aptidão física associados à saúde (ApFS) em crianças. Os dados provêm de 96 pares de gêmeos monozigóticos e dizigóticos do arquipélago dos Açores (Portugal) cuja idade varia entre os 6 e os 12 anos. A ActF foi estimada com base no questionário de Godin e Shephard e a ApFS foi avaliada a partir da bateria de testes Prudential Fitnessgram. O cálculo das estimativas da influência genética e do envolvimento comum e único foi efectuado com base em procedimentos bem referenciados na literatura. Os resultados sugerem que cerca de 25% das diferenças interindividuais nos níveis de ActF podem ser atribuídas a efeitos genéticos. Já os valores de ApFS evidenciam um maior contributo génico: 32% na prova do trunk lift, 53.4% na prova de push-up, 38.4% na prova de curl-up, 58.2% na corrida-marcha da milha e 88% no índice de massa corporal. Em conclusão pode referir-se que os efeitos genéticos que governam as diferenças interindividuais são de magnitude baixa a moderada, exceptuando o índice de massa corporal. De particular importância é o efeito do envolvimento comum. Este último dado deve ser considerado de modo importante no sentido de consolidar a relevância da família, sobretudo dos progenitores na promoção de um estilo de vida activo e saudável.

The purposes of this study were to estimate the importance of genetic and environmental factors in physical activity (ActF) and health-related physical fitness (ApFS) levels of children. Data comes from 96 twin monozygotic and dizygotic pairs aged 6-to-12 years of the Azores Islands (Portugal). Physical activity was estimated with the Godin & Shephard questionnaire, and the ApFS was evaluated with the Prudential Fitnessgram test battery. Genetic factors, common and unique environmental estimates were calculated with well-known formulas. About 25% of the total variance in ActF was explained by genetic differences among subjects. In ApFS genetic effects were of the following magnitude: 32% for curl-up, 53.4% for trunk-lift, 38.4% for curl-up, 58.2% for 1 mile run-walk, and 88% for body mass index. In conclusion we may state that the magnitude of genetic effects are low to moderate, with exception of body mass index. An emphasis must be stated for the importance of common environmental effects. This fact should be regarded as an issue to pinpoint the importance of familial environment, especially the relevance of parents in their promotion of active and healthy lifestyles among family members.

Aspectos genéticos da actividade física e aptidão física associada à saúde. Estudo em gêmeos dos 12 aos 40 anos de idade do arquipélago dos Açores (Portugal) / Genetic aspects of physical activity and health related physical fitness. A study in twins aged 12-to-40 years from the Azores (Portugal) islands

Este estudo tem como propósitos estudar aspectos da variação genética nos níveis de actividade física e aptidão física associada à saúde de gémeos do arquipélago dos Açores (Portugal). Com base numa amostra de 64 pares de gémeos dos 12 aos 40 anos pertencentes às 8 das 9 ilhas, foramavaliados (1) os níveis de actividade física com base no questionário de Baecke, (2) e os valores da aptidão física referenciados pela saúde providenciados pela bateria Fitnessgram. Os procedimentosestatísticos utilizados foram os usuais neste tipo de análises, bem como foram calculadas as estimativas de heritabilidade (h2). Todos os cálculos foram efectuados nos programas SPSS 10 e Systat 10. Os resultados mostraram estimativas de h2 moderadas a elevadas para os níveis de actividade física, entre 23.4% e 77%. Um quadro algo semelhante de resultados ocorreu para os diferentes testes marcadores da aptidão física - entre 30% e 80%. As conclusões remetem-nos para diferenças genéticas moderadas a elevadas entre sujeitos e que são responsáveis pela heterogeneidade nos valores de actividade física e aptidão física. Contudo, é também aberta uma porta à influência ambiental nos programas deeducação física e desportiva, para além de outros elementos.

This study aims at the investigation of the genetic variance in the levels of physical activity and health related physical fitness of twins for the archipelago of Azores (Portugal). Based on a sample of 64 twin pairs aged 12 to 40 years from 8 of the 9 islands, we evaluated (1) their levels of physical activity based in the Baecke questionnaire, as well as (2) their health related physical fitness values, as provided by the Fitnessgram test battery. Standard statistical procedures were used in these types of analysis, aswell as heritabilities estimates (h2). All computations were done in SPSS 10 and SYSTAT 10. Results showed moderate to high h2 estimates for physical activity, between 23.4% and 77%. A similar picture was observed in the marker test for physical fitness - between 30% and 80%. We may conclude that moderate to high genetic differences among subjects are responsable for the heterogeneity of observed values in physical activity and physical fitness. It should also be mentioned that environmental factorsare also important, opening an important window for the physical and sportive education, as well as for other environmental factors.

Aspectos genéticos da prática desportiva: um estudo em gêmeos / Genetic aspects of sports practice: a twin stydy

Este estudo é percorrido por dois propósitos fundamentais: a) apresentar, ainda que de modo breve, aspectos da metodologia de genética quantitativa aplicados ao estudo de fenótipos de interesse dos cientistas das iências do Desporto; e b) aplicar tais técnicas e procedimentos em gêmeos monozigóticos (MZ) e dizigóticos (DZ) para determinar a presença de efeitos genéticos nos seus índices de prática desportiva. A amostra é constituida por 104 pares de gêmeos, 40 MZ e 64 DZ, cuja média de idades é 17,30 mais ou menos 5,82 e 17,86 mais ou menos 8,12, respectivamente. O índice de prática desportiva foi obtida a partir do questionário de Baecke et alii (1982). Os procedimentos estatísticos compreendem tabelas de contingência, correlaçöes tetracóricas, taxas de concordância "probandwise", bem como ajustamento de modelos univariados gemelares. Os programas estatísticos utilizados foram o SPSS 9.0 e o Mx. Os principais resultados e conclusöes foram os seguintes: a) é evidente a presença de forte agregaçäo familiar nos valores de prática desportiva; b) estes valores säo mais fortes nos gêmeos MZ do que nos gêmeos DZ, e mais elevados nos meninos do que nas meninas...

Fetus in fetu: presentación de un caso y revisión de la literatura / Fetus in fetu: presentation of case and review

Se reportó el caso de una paciente femenina de 3 meses de edad referida de la ciudad de La Ceiba, con historia de un mes de evolución de vómitos post-prandiales y distensión abdominal. En la última semana la madre nota tumoración en hipocondrio derecho. La tomografía axial computarizada reporta tumoración heterogenea de 12.1 cm x 8.8 cm con múltiples calcificaciones en su interior compatible con teratoma. Durante la intervención quirúrgica se realizó el diagnóstico de "Fetus in Feto" el cual fue confirmado por patología. "Fetus in fetu" es una anormalidad congenita in-usual, existen 80 casos reportados en todo el mundo y este es el primer caso reportado en nuestro país

Juvenile Huntington's disease confirmed by genetic examination in twins

Early-onset Huntington's disease (HD) occurs in approximatley 10 per cent of HD's cases. We report juvenile HD in phenotypically identical twins, evaluated by history, clinical and neurologic examination, minimental state examination, blood laboratory exams, cerebrospinal fluid examination, skull computed tomography, and genetic examination for HD. Patients had the akinetic-rigid variety (Westphal variant) of the disease and paternal inheritance. The laboratory workup confirmed the clinical diagnosis of HD, which adds this report to the rare cases of HD in twins reported in the literature.

Genetic effect on apgar score

Intraclass correlation coefficients for one- and five-min Apgar scores of 604 twin pairs born at a southeastern Brazilian hospital were calculated, after adjusting these scores for gestational age and sex. The data support a genetic hypothesis only for 1-min Apgar score, probably because it is less affected by the environment than 4 min later, after the newborns have been under the care of a neonatology team. First-born twins exhibited, on average, better clinical conditions than second-born twins. The former showed a significantly lower proportion of Apgar scores under seven than second-born twins, both at 1 min (17.5 per cent vs. 29.8 per cent) and at 5 min (7.2 per cent vs. 11.9 per cent). The proportion of children born with "good" Apgar scores was significantly smaller among twins than among 1,522 singletons born at the same hospital. Among the latter, 1- and 5-min Apgar scores under seven were exhibited by 9.2 per cent and 3.4 per cent newborns, respectively.