scholarly journals Search for Genomic Alterations in Monozygotic Twins Discordant for Cleft Lip and/or Palate

2009 ◽  
Vol 12 (5) ◽  
pp. 462-468 ◽  
Author(s):  
Jane W. Kimani ◽  
Koh-ichiro Yoshiura ◽  
Min Shi ◽  
Astanand Jugessur ◽  
Danilo Moretti-Ferreira ◽  
...  
Keyword(s):  
Cleft Lip ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Comparative Genomic ◽  
Genomic Alterations ◽  
Molecular Abnormalities ◽  
Changes Detection ◽  
The Stability ◽  
Discordant Genotype ◽  
Paired Analysis

AbstractPhenotypically discordant monozygotic twins offer the possibility of gene discovery through delineation of molecular abnormalities in one member of the twin pair. One proposed mechanism of discordance is postzygotically occurring genomic alterations resulting from mitotic recombination and other somatic changes. Detection of altered genomic fragments can reveal candidate gene loci that can be verified through additional analyses. We investigated this hypothesis using array comparative genomic hybridization; the 50K and 250K Affymetrix GeneChip® SNP arrays and an Illumina custom array consisting of 1,536 SNPs, to scan for genomic alterations in a sample of monozygotic twin pairs with discordant cleft lip and/or palate phenotypes. Paired analysis for deletions, amplifications and loss of heterozygosity, along with sequence verification of SNPs with discordant genotype calls did not reveal any genomic discordance between twin pairs in lymphocyte DNA samples. Our results demonstrate that postzygotic genomic alterations are not a common cause of monozygotic twin discordance for isolated cleft lip and/or palate. However, rare or balanced genomic alterations, tissue-specific events and small aberrations beyond the detection level of our experimental approach cannot be ruled out. The stability of genomes we observed in our study samples also suggests that detection of discordant events in other monozygotic twin pairs would be remarkable and of potential disease significance.

scholarly journals Copy number variation analysis of twin pairs discordant for cleft lip with or without cleft palate

2019 ◽  
Vol 33 ◽  
pp. 205873841985587
Author(s):  
Luca Scapoli ◽  
Francesco Carinci ◽  
Annalisa Palmieri ◽  
Francesca Cura ◽  
Alessandro Baj ◽  
...  
Keyword(s):  
Cleft Palate ◽  
Copy Number ◽  
Large Scale ◽  
Cleft Lip ◽  
Small Sample Size ◽  
Copy Number Variants ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Small Sample ◽  
High Level

Non-syndromic cleft lip with or without cleft palate (nsCL/P) is a frequent orofacial malformation. The comparison of concordance rate observed in monozygotic and dizygotic twins supports high level of heritability and a strong genetic component. However, phenotype concordance for orofacial cleft in monozygotic twins is about 50%. The aim of the present investigation was to detect postzygotic events that may account for discordance in monozygotic twins. High-density SNP microarrays hybridization was used to genotype two pairs of monozygotic twins discordant for nsCL/P. Discordant SNP genotypes and copy number variants were analyzed to identify genetic differences responsible of phenotype discrepancy. A number of differences were observed, none involving known nsCL/P candidate genes or genomic regions. Considering the limitation of the study, related to the small sample size and to the large-scale investigation method, the results suggest that the detection of discordant events in other monozygotic twin pairs would be remarkable and warrant further investigations.

Natal Teeth in Monozygotic Twins with Van der Woude Syndrome

1992 ◽  
Vol 29 (3) ◽  
pp. 279-281 ◽  
Author(s):  
Joseph H. Hersh ◽  
Gerald D. Verdi
Keyword(s):  
Cleft Lip ◽  
Autosomal Dominant ◽  
Clinical Manifestations ◽  
Monozygotic Twins ◽  
Low Frequency ◽  
Monozygotic Twin ◽  
Van Der Woude Syndrome ◽  
Lower Lip ◽  
Natal Teeth ◽  
Monozygotic Twin Pair

The second monozygotic twin pair concordant for Van der Woude syndrome Is reported. Clinical manifestations of this autosomal dominant clefting syndrome Included bilateral lower lip pits, cleft lip, and cleft palate. Both sibs were found to have a natal tooth. No other cases of Van der Woude syndrome with this feature have been described previously. It is uncertain whether the presence of a natal tooth in this instance represents a low-frequency association of this disorder. However, it appears more likely that its occurrence was incidental, since natal teeth have been reported before in twin pairs as an isolated finding.

Comparison of Craniofacial and Dentoalveolar Morphologies of Three Japanese Monozygotic Twin Pairs with Cleft Lip and/or Palate Discordancy

1998 ◽  
Vol 35 (2) ◽  
pp. 173-180 ◽  
Author(s):  
Keiji Moriyama ◽  
Nobuyoshi Motohashi ◽  
Atsushi Kitamura ◽  
Takayuki Kuroda
Keyword(s):  
Growth And Development ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Surgical Closure ◽  
Bilateral Cleft Lip ◽  
Morphological Differences ◽  
Cast Analysis ◽  
Dental Cast

Objective In this study, we analyzed the craniofacial and dentoalveolar morphologies of three pairs of monozygotic twins discordant for cleft lip and/or palate (CL/P) in order to evaluate the effects of environmental factors on growth and development. Design Craniofacial and dentoalveolar morphologies revealed by analyses of cephalograms and dental casts were compared for each pair of twins discordant for CUP. Subjects In case 1, the subjects were 10-year-old male twins, one of whom had a repaired unilateral cleft lip and alveolus and one of whom had an unrepaired unilateral cleft lip. In case 2, the subjects were 13-year-old female twins, one of whom had a repaired bilateral cleft lip and palate and one of whom had an unrepaired unilateral cleft lip. In case 3, the subjects were 9-year-old female twins, one of whom had a repaired unilateral cleft lip and palate and one of whom had no cleft. Results Cephalometric analysis disclosed distinguished intrapair differences in the maxillary and mandibular morphologies in cases 2 and 3. However, the tooth axes of the incisors in operated subjects were consistently influenced in all three cases. Dental cast analysis indicated that the shapes and sizes of the alveolar and dental arches in the operated subjects were affected in case 2 and, more severely, in case 3, while they looked fairly similar in case 1. Conclusions Cephalometric and dental cast analyses demonstrated characteristic intrapair differences between the twins discordant for CL/P according to each cleft type. These morphological differences indicate that surgical closure of clefts may have considerable effects on craniofacial and dentoalveolar growth and development in CL/P patients.

Growth Study Including Stereophotogrammetry of a Pair of Monozygotic Twins, One Having a Cleft Lip and Palate

1987 ◽  
Vol 14 (2) ◽  
pp. 73-84 ◽  
Author(s):  
P. Burke ◽  
C. Hughes
Keyword(s):  
Soft Tissue ◽  
Cleft Lip ◽  
Cleft Lip And Palate ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Tissue Growth ◽  
Facial Growth ◽  
Growth Study ◽  
The Face ◽  
Growth Changes

This report is a serial growth study of a pair of monozygotic twin boys, one of whom suffered from a bilateral cleft of the lip and a unilateral cleft of the palate. Annual records for height and weight were registered from seven years eight months to 18 years 0 months. Soft tissue facial growth was also measured annually using short base stereophotogrammetry (Burke, 1967). Growth and development of the dentition was recorded as orthodontic study models at less frequent intervals. Measurements derived from the facial maps allowed not only measurement of soft tissue growth changes in the face, but also of surgical change to both lips related to an Abbe flap procedure carried out for the cleft twin. All changes are compared with those occurring in his monozygotic twin.

Associations between insulin-like growth factor-I (IGF-I), IGF-binding protein-1, insulin and other metabolic measures after controlling for genetic influences: results from middle-aged and elderly monozygotic twins

1997 ◽  
Vol 153 (2) ◽  
pp. 251-257 ◽  
Author(s):  
Y Hong ◽  
K Brismar ◽  
K Hall ◽  
N L Pedersen ◽  
U de Faire
Keyword(s):  
Genetic Variation ◽  
Growth Factor ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Genetic Influences ◽  
Insulin Like Growth Factor ◽  
Factor I ◽  
Igf I ◽  
Igf Binding ◽  
Igf Binding Protein

Abstract It has previously been shown that the serum levels of insulin-like growth factor-I (IGF-I), IGF-binding protein-1 (IGFBP-1), and insulin are influenced by genetic effects to various degrees. From a clinical and preventive point of view, however, it is important to identify potentially modifiable non-genetic factors influencing the levels of these measures. Because monozygotic twin pairs share the same genetic background, differences in phenotypic levels within monozygotic twin pairs are believed to be due to non-genetic influences. Accordingly, the associations between intrapair differences in one phenotype and intrapair differences in another phenotype are also due to non-genetic influences. The present sample of 97 pairs of monozygotic twins from the population-based Swedish Adoption/Twin Study of Aging (SATSA) provided the opportunity to assess non-genetic influences on the levels of IGF-I, IGFBP-1, and insulin. Several metabolic measures were found to account for the variation of IGF-I, IGFBP-1, and insulin after controlling for the genetic influences. IGFBP-1 and glucose were significant predictors for the levels of IGF-I. IGFBP-1 and glucose together explained about one quarter of the non-genetic variation of IGF-I. However, when IGFBP-1 was dropped from the regression model, insulin was the only independent predictor of IGF-I, and explained about 19% of the non-genetic variation for IGF-I. For IGFBP-1, insulin and IGF-I were the significant non-genetic predictors. Insulin and IGF-I explained about 28 and 8% respectively of the non-genetic variation for IGFBP-1, while for insulin, IGF-I, triglycerides, body height, glucose, and body mass index (BMI) explained approximately 20, 12, 6, 5 and 5% respectively of the non-genetic variation. Journal of Endocrinology (1997) 153, 251–257

scholarly journals Articulatory and acoustic inter-speaker variability in the production of German vowels

2010 ◽  
Vol 52 ◽  
pp. 19-42
Author(s):  
Melanie Weirich
Keyword(s):  
Genetic Similarity ◽  
Strong Influence ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Shared Environment ◽  
Acoustic Similarity ◽  
Speaker Variability ◽  
Electromagnetic Articulography ◽  
Shared Time ◽  
The Impact

This study examines articulatory and acoustic inter-speaker variability in the production of the German vowels /i/, /u/ and /a/. Our subjects are 3 monozygotic twin pairs (2 female and 1 male pair) and 2 dizygotic female twin pairs. All of them were born, raised and are still living in Berlin and see their twin brother or sister regularly. We assume that monozygotic twins that are genetically identical and share the same physiology should be more similar in their articulation than dizygotic twins but that the shared time and social environment of twins, regardless of their genetic similarity, also plays a crucial role in the acoustic similarity of twins. Articulatory measurements were made with EMA (Electromagnetic Articulography) and the target positions of the produced vowels were analyzed. Additionally, the formants F1-F4 of each vowel were measured and compared within the twin pairs. Our data seems to point out the importance of a shared environment and the strong influence of learning over the anatomical identity of the monozygotic twins regarding the production of vowels. But, additional results suggest (1) the impact of physiology on the production of a vowel following a velar consonant and (2) the interaction of physiology and stress in inter-speaker variability.  

On the Statistical Significance of one Pair of Monozygotic Twins in Clinical Genetics

1963 ◽  
Vol 12 (4) ◽  
pp. 317-323
Author(s):  
L. Gedda
Keyword(s):  
Twin Pair ◽  
Statistical Significance ◽  
Statistical Treatment ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Clinical Genetics ◽  
Pair Comparison ◽  
Monozygotic Twin Pair ◽  
Development Result

SUMMARYA case of one twin pair concordant or discordant as to a given disease is always very important for Clinical Genetics, especially when it is monozygotic. In Clinical Genetics, isolated pairs occur to the physician, and the diagnosis must therefore be based on intra-pair comparison. The statistical treatment of the case must consider the fact that a concordant monozygotic twin pair represents a statistical universe rather than a statistical unit. This entails taking into account many traits concerning the time of onset, the symptoms, development, result of treatment, etc. Suggestions are made for the statistical treatment of such cases.

Mental and Motor Development in Monozygotic Co-Twins With Dissimilar Birth Weights

PEDIATRICS ◽  
1974 ◽  
Vol 53 (6) ◽  
pp. 884-889
Author(s):  
Toshio Fujikura ◽  
Luz A. Froehlich
Keyword(s):  
Birth Weight ◽  
Human Brain ◽  
Motor Development ◽  
Monozygotic Twins ◽  
Monozygotic Twin ◽  
Mental Development

Developmental measures in 125 monozygotic twin sets with unequal birth weights between co-twins were studied. There were no significant differences between co-twins in the Bayley Mental and Motor Scores at 8 months nor the Stanford-Binet IQ at 4 years. A reportedly higher IQ for the heavier of monozygotic twins was not confirmed in this study, even among pairs with large birth-weight differences. Although the effects of nutrition on the mental development of the fetus are currently of great concern, these data suggest that the developing human brain seems to have a strong resistance to intrauterine deprivation.

Genomic characterisation of multiple myeloma: study of a Portuguese cohort

2021 ◽  
pp. jclinpath-2020-207204
Author(s):  
Alexandra Couto Oliveira ◽  
Ilda Patrícia Ribeiro ◽  
Luís Miguel Pires ◽  
Ana Cristina Gonçalves ◽  
Artur Paiva ◽  
...  
Keyword(s):  
Multiple Myeloma ◽  
Clinical Practice ◽  
Prognostic Value ◽  
Clinical Presentation ◽  
Comparative Genomic Hybridisation ◽  
Comparative Genomic ◽  
Genomic Alterations ◽  
Genomic Complexity ◽  
Genome Wide ◽  
Trisomy 9

Multiple myeloma (MM) genomic complexity reflects in the variable patients’ clinical presentation. Genome-wide studies seem to be a reasonable alternative to identify critical genomic lesions. In the current study, we have performed the genomic characterisation of a Portuguese cohort of patients with MM by array comparative genomic hybridisation. Overall, the most frequently detected alterations were 13q deletions, gains of 1q, 19p, 15q, 5p and 7p and trisomy 9. Even though some identified genomic alterations were previously associated with a prognostic value, other abnormalities remain with unknown, but putative significance for patients’ clinical practice. These genomic alterations should be further assessed as possible biomarkers.

Sign in / Sign up

Export Citation Format

Share Document