Murray 1 jonathan mill 2 0 st andrews academic centre. Birth weight discordant twins have increased prenatal mortality and neonatal morbidity. His life pattern was compared with that of his nonpsychotic cotwin, and his early characteristics and. The discordant twin discotwin consortium was established for this goal. An unconformity characterized by lack of parallelism between strata which touch without fusion explanation of discordant.
Wholeexome sequencing in nine monozygotic discordant twins article pdf available in twin research and human genetics 1901. Placental weight in severely discordant twins is lower for the smaller twin in dichorionic pregnancies, and total placental weight is decreased for monochorionic discordant twins. This analysis approach was conducted for i all twin pairs discordant for major psychosis n 22 pairs, 44 individuals, then separately for ii the sz discordant twins n 11 pairs, 22 individuals and iii the bd discordant twins n 11 pairs, 22 individuals. None of the twins had selfreported chronic rheumatic joint disease at the time of blood collection. Genomic and epigenomic analyses of monozygotic twins. Discordant twin growth in dichorionic pregnancies was found to be associated with preterm birth. To obtain the numbers of pairs, especially monozygotic mz twin pairs, necessary for indepth studies while also allowing for replication, twin studies worldwide need to pool their resources. First, we summarise the advantages and strengths of this design over the classical matched casecontrol study. It is well established that epigenetic states can contribute to phenotypic variation, including disease.
This high discordance is often explained by the role of yet unknown environmental, random, and epigenetic factors. The suggested results are not a substitute for clinical judgment. It is a common 1% and often familial disease with a discordance rate of 50% in monozygotic twins. For discordant twins, 3 studies of 6008 total pregnancies have implicated discordance as a factor for adverse perinatal outcome. Find out information about growth discordant twins. Aug 26, 2008 i have former 26 weeker boygirl twins who are 17 months actual, 14 months adjusted. This manuscript reports the results of the metaanalysis of this. Cerebrospinal fluid microglia and neurodegenerative markers in twins concordant and discordant for psychotic disorders, european archives of psychiatry and clinical neuroscience, 2017, pp. Increased dna methylation variability in rheumatoid arthritis.
Schalkwyk 2 sheena owens 1 anna georgiades 1 fergus kane 1 sridevi kalidindi 1 marco picchioni 0 1 eugenia kravariti 1 timothea. Discordant zika virus findings in twin pregnancies. Discordant definition of discordant by merriamwebster. Discordancy is defined as a difference of 15% or more in the. Pdf there is a lack of consensus on the definition and diagnosis of discordance in twin pregnancies. Despite their singular origin, monozygotic twin pairs often display discordance for complex disorders including schizophrenia.
Cerebrospinal fluid microglia and neurodegenerative markers. We identified 14 risk factors for divergent growth that can be categorized as maternal, fetal. Currently benjamin is crawling everywhere, eating stage 2 foods very well, and reducing the amount of time he needs to sleep. Among monozygotic twins discordant for schizophrenia, the twins with the illness tend to perform worse than the unaffected twins on most cognitive and personality measures 59. Geneticepidemiological studies on monozygotic mz twins have been used for decades to tease out the relative contributions of genes and the environment to a trait. Discordant twins as a tool to unravel the aetiology of. Is discordant growth in twins an independent risk factor. Through genomewide analysis of dna methylation in diseasediscordant monozygotic twins, we have identified a differentially variable dna methylation signature, in the absence of differential methylation in rheumatoid arthritis. Although there are multiple publications on the increased morbidity and mortality rates with discordant growth, there is a paucity of reports on how to manage them optimally and deliver them in a timely manner. Among discordant twins who do not meet the adir diagnostic criteria for autism i. The goal of this study is to identify genomic and epigenomic differences between a pair of twins.
Dna methylation signatures of monozygotic twins clinically. It is clear that diagnosis of discordant growth has improved due to the use of serial ultrasound. Discordant twins with the smaller baby appropriate for gestational age unusual manifestation of superfoetation. The weight of the placenta of the smaller fetus in severely discordant dichorionic twins with separate placentas and the total placental weight in. In addition, another pair of discordant fraternal twins was described. Discordant growth in twins contributes significantly to rates of perinatal morbidity and mortality.
Is discordant growth in twins an independent risk factor for. Discordant growth alone is not an indication for preterm birth. The control group consisted of 27 nondiscordant twins. Stepwise approach to the sonographic evaluation in twin pregnancies. Marked vascular communication between separated dichorionic diamniotic placentas article pdf available in twin research 64. Discordant twins with the smaller baby appropriate for. These rates vary according to chorionicity, timing of onset and severity.
Diagnosis, evaluation and management approximately 16% of twin gestations have discordance of at least 20%. Wholeexome sequencing in nine monozygotic discordant twins. The gradual development of paranoid schizophrenia was described in an mz male twin who later recovered completely from his illness. Results monozygotic twins discordant for als show no evidence of germline epimutation at known als genes ten individuals were included in this study. Morbidity and mortality of discordant twins up to 34 weeks of. Journal of pediatric ophthalmology and strabismus as part of the genes in myopia gem study, the authors describe a pair of monozygotic twins who presented with discordant hypermetropia. Differentially methylated sites in whole blood from twins discordant for ssc.
View the article pdf and any associated supplements and figures for a period of 48 hours. Differences in frontal and limbic brain activation in a. Monozygotic mz twins share nearly all of their genetic variants and many similar environments before and after birth. The concordance and heritability of type 2 diabetes in. My daughter has always been a lot smaller than my son shes now almost 18 pounds and hes 23 pounds. Using a qualitative monozygotic mz twin differences design we explored whether adolescent mz twins report discordant peer relationships and, if so, whether they perceive them as causes, consequences or correlates of discordant behaviour. This finding supports the importance of epigenetic variability as an emerging component in autoimmune disorders.
Managing twins discordant for fetal anomaly rustico 2005. Respiratory distress syndrome rds was more common in discordant than concordant sga twins 10. Asd phenotypegenotype associations in concordant and. In both mz and dz bmidiscordant pairs, the heavier cotwins reported being less capable of regulating their food intake optimally than their leaner cotwins, mainly due to frequent overeating. Genome and epigenome analysis of monozygotic twins. Zika virus was detected in only 1 twin on neonatal urine specimen. The definition, diagnosis, and management of growth. Journal of pediatric ophthalmology and strabismus as part of the genes in myopia gem study, the authors describe a pair of monozygotic twins who. The mode of delivery in discordant twins remains controversial. Birth weight of the smaller twin grams birth weightof the larger twin grams birth weight discordance % a difference of 18% or greater in birth weight should prompt more intensive fetal monitoring 1. In seven pairs both twins were females, and all were discordant for psychosis.
Schalkwyk 2 sheena owens 1 anna georgiades 1 fergus kane 1 sridevi kalidindi 1 marco picchioni 0 1 eugenia kravariti 1 timothea toulopoulou 1 robin m. Approximately 16% of twin gestations have discordance of at least 20%. Both liver fat concordant and discordant groups were equally discordant for bmi mean bmi difference 5. Integrative analysis of dna methylation in discordant twins. Detailed neurological assessment using the new ballard scoring 1, was done on the second day. Discordant growth in twins obstetrics and gynecology wiley. Genomewide blood dna methylation alterations at regulatory. Oct 25, 2014 aneuploidy screening 1st trimester screen. My son was born at 2 lbs and my daughter at 1 lb 7 oz. Gut microbiota from twins discordant for obesity modulate metabolism in mice vanessa k.
Eating behaviors in healthy young adult twin pairs. Because the full draft board test battery is administered only to males, the analyses focus on the 12 male twins who were discordant for psychosis. Differences at the epigenetic level may account for such discordances. Monozygotic twins n 19 were analyzed first, followed by a replication with the data for dizygotic twins n 8. Human molecular genetics diseaseassociated epigenetic changes in monozygotic twins discordant for schizophrenia and bipolar disorder emma l. Nevertheless, mz twins are sometimes discordant for common complex diseases. The main aim of this study was to ascertain the performance of bw and ultrasound efw discordance in the prediction of perinatal loss in twin. Integrative analysis of dna methylation in discordant. Studying twins discordant for cp allows genetic and environmental components to be partitioned from each other and provides a unique opportunity to evaluate the importance of nonshared environmental factors such as umbilical cord or placental function during early development in isolation. Cerebrospinal fluid microglia and neurodegenerative. Studies of psychotic and nonpsychotic siblings 14 and pairs of twins discordant for psychoses 59 have identified risk factors for psychoses. To estimate whether discordant growth is associated with adverse perinatal outcomes in twins after adjusting for growth restriction.
Information and translations of discordant in the most comprehensive dictionary definitions resource on the web. In 15 pairs, both twins were males, and 12 were discordant for psychosis. His life pattern was compared with that of his nonpsychotic co. University of milano, department of obstetrics and gynaecology, ospedale v. The probability of monozygotic trisomy 18 twinning and the mechanisms for phenotypic discordance in trisomic twins is discussed. We gathered freeresponse questionnaire data from 497 families and conducted indepth telephone interviews with 97 of them. Medical history of discordant twins and environmental. We recruited a pair of mmddiscordant monozygotic twins with familial occurrence of mmd as shown in fig. Highspecificity bioinformatics framework for epigenomic. Growth discordant twins article about growth discordant. Growth discordant twins definition of growth discordant. The first case of liveborn monozygotic trisomy 18 twins was reported in 1989 and we report a second case in which striking phenotypic discordance existed.
Twins with birth weight discordance of more than 20%, calculated from the weight of the larger twin 1. Although familial occurrence of mmd comprises approximately. Intrapair birthweight discordance in twins bioline international. Reproducibility of microbiota transplants from discordant twins we surveyed data collected from 21 to 32yearold female twin pairs n 1539 enrolled in the mis souri adolescent female twin study moafts. Growth discordance in multiple pregnancies due to placental insufficiency, twin to twin transfusion or aneuploidy need to be differentiated from superfoetation. Premorbid functioning in a national population of male. An international census survey volume 40 issue 34 i. Circulating microrna expression profiling in the mmd discordant monozygotic twins and nontwin cohorts. Furthermore, the heavier cotwins reported augmented disinhibited eating, bingeeating scores and body dissatisfaction. Genome and epigenome analysis of monozygotic twins discordant. On the other hand, the discordant mz and dz twins who received an autism. Discordant twins were tested for both differential dna methylation and methylation variability between rheumatoid arthritis and healthy twins.
Blickstein skip to main content accessibility help we use cookies to distinguish you from other users and to provide you with a better experience on our websites. For the replication with bisulfite pyrosequencing see the statistical analysis for validation section in the methods an additional six healthy mz twin pairs discordant for acpa and six mz twin pairs discordant for. Circulating mirnome profiling in moyamoya diseasediscordant. In twin studies, if a trait is genetic, monozygotic twins should be 100% concordant, dizygotic twins should be 50% concordantdiscordant. To our knowledge, this study constitutes the first analysis of snps, cnvs, indels, and dmrs to directly observe the differences resulting from genetic and environmental factors in monozygotic twins discordant for congenital renal agenesis.
Diseaseassociated epigenetic changes in monozygotic twins. Superfoetation implies fertilization and subsequent development of an ovum when a foetus is already present in the uterus. Jan 19, 2007 the first of the twins twin a weighed 980 grams and the next baby twin b weighed 2160 grams. The goal of this study is to identify genomic and epigenomic differences between a pair of twins discordant for a form of congenital heart. This is a pdf file of an unedited manuscript that has been accepted for publication. We performed genomewide dna methylation analysis in whole blood from 27 twin pairs discordant for ssc table 1. Monozygotic mz twins share nearly all of their genetic variants before and after birth. To date, few studies have empirically tested for epigenetic differences between mz twins discordant for. However, they can also show phenotypic discordance for a wide range of traits. Weight discordance and perinatal mortality in twins. Discordant article about discordant by the free dictionary. Monozygotic twins discordant for schizophrenia springerlink.
The definition, diagnosis, and management of growth discordant twins. This was a retrospective, hospitalbased cohort study of twin gestations with 2 live births delivered at 24 weeks or later from 1992 to 2001. We conclude that ultrasound surveillance of twin gestations. Twin gestations when compared to singletons are associated with higher perinatal morbidity and mortality. First, cases of monozygotic twins discordant for congenital renal agenesis are very rare. Acpapositive healthy discordant twins tested positive for acpa high concentration, 75 auml while their sibling tested negative for acpa. Birth weight discordant twins have increased prenatal mortality and. Also, none of these twins was identified with a discharge ra diagnosis or other rheumatic. This limits opportunities for early intervention that could otherwise improve longterm outcomes. Countrymen, butchers, drovers, hawkers, boys, thieves, idlers, and vagabonds of every low grade, were mingled together in a mass. Discordant twins may be at increased risk for retinopathy of prematurity rop because of factors related to their unequal growth. Cerebral palsy cp is a clinical description for a group of motor disorders that are heterogeneous with respect to causes, symptoms and severity. One of two identical or similar people, animals, or things. Eleni tzachrista, md, jose sierra, md, philippe jeanty, md, phd.
Both twins had birth weights that were appropriate for gestational age 2550 grams and 2650 grams. The utility of diseasediscordant twins in epigenetic epidemiological studies of complex disease was highlighted by a recent analysis of dna methylation differences between mz twins discordant for systemic lupus erythematosus. Twentyseven 27,3% of 99 twin pairs born in our clinic had a birth weight difference of more than 20%. Genomewide dna methylation was assessed in 79 monozygotic twin pairs discordant for rheumatoid arthritis using the humanmethylation450 beadchip array illumina. Differences in frontal and limbic brain activation in a small. In this study of a pair of monozygotic twins discordant for congenital renal agenesis, the genomic profile was analyzed from a set of blood samples using highthroughput exomecapture sequencing to detect singlenucleotide polymorphisms snps, copy number variations cnvs, and insertions and deletions indels. Do mz twins have discordant experiences of friendship. Congenital heart disease chd is the leading noninfectious cause of death in infants.
Delivery decisions in discordant dcda twins with single. The importance of a systematic approach to twin pregnancies. Pdf wholeexome sequencing in nine monozygotic discordant twins. Phenotypic discordance in mz twins has traditionally been ascribed to nonshared environmental factors acting after birth, however recent data indicate that this explanation is far too simple. In order to establish a protocol considering the definition, diagnosis, and management of growthdiscordant twin gestations, a questionnaire was sent to 96 authors of twinrelated obstetric articles. The total intelligence quotient iq in the asd discordant twin sample ranged from 40 to 121 m89. Introduction both babies share one placenta of twins in the uk have mc placentas recent increase in multiple pregnancies due to art particular challenges. The placentas were discordant for zikv pcr testing, with the positive placenta corresponding to the positive twin, and the negative placenta corresponding to the negative twin. Samesex twin pairs accounted for 60% of all cases of birthweight discordance. Gut microbiota from twins discordant read the full article. Then, we draw attention to the use of this method in bipolar disorder, revising previous discordanttwin studies. Gut microbiota from twins discordant read the full.
This editorial focuses on discordant twins as a valuable epidemiological design for psychiatric aetiological research. The study of mz twins discordant for schizophrenia can shed light on important experiential factors in the development of at least some cases of schizophrenia. Premorbid functioning in a national population of male twins. Then, we draw attention to the use of this method in bipolar disorder, revising previous discordant twin studies. Circulating mirnome profiling demonstrated distinct 2 groups separated by mmd and healthy control. Twin gestations were classified as small for gestational age sga if one or. Multiple sclerosis ms is an inflammatory, demyelinating disease of the central nervous system with a modest concordance rate in monozygotic twins, which strongly argues for involvement of.