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Fraternal Twin

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Journal Article
Demography (2006) 43 (4): 747–769.
Published: 01 November 2006
...Guang Guo; Yuying Tong Abstract We carried out two distinct types of genetic analysis with data from the National Longitudinal Study of Adolescent Health. The first was a non-DNA twin analysis using monozygotic (identical) and same-sex dizygotic (fraternal) twins. The second analysis investigates...
Journal Article
Demography (2011) 48 (4): 1517–1533.
Published: 16 August 2011
... population registry, we estimate Cox proportional hazards models that describe similarity in the timing of smoking desistance among adult twin pairs. We show that identical twin pairs are significantly more likely to quit smoking within a similar time frame compared with fraternal twin pairs. Importantly, we...
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Journal Article
Demography (1999) 36 (4): 421–428.
Published: 01 November 1999
... relatedness (Plomin, DeFries, and McCleam 1990). The most common design is to compare pairs of iden- tical twins with pairs of fraternal twins. The former have 100% of their genes in common; the latter, like any pair offull siblings, have, on average, 50% in common. The researchers assume, crucially...
Journal Article
Demography (2010) 47 (2): 327–343.
Published: 01 May 2010
...; Wang et al. 2009). The key support that autism is a genetic disorder arises from the reported difference in concordance rates for autism in identical and fraternal twin pairs, and a high recurrence risk in siblings. There is no reason to believe that any one of these frameworks is wrong...
Journal Article
Demography (2001) 38 (3): 437–447.
Published: 01 August 2001
.... Monozygotic (MZ; identical) twins are 100% genetically re- lated; dizygotic (DZ; fraternal) twins, nontwin siblings, and other first-degree relatives have an expected genetic corre- lation equal to roughly half that of monozygotic twins. Simple behavioral genetics models capitalize on the natural experiment...
Journal Article
Demography (2012) 49 (1): 151–174.
Published: 19 January 2012
... of fraternal twins varies, and several risk factors may contribute to an increase in their incidence. 4 In the literature, two concerns are related to using multiple births as an instrument for fertility. First, multiple births have a higher incidence among mothers undergoing fertility treatments and among...
Journal Article
Demography (2017) 54 (1): 71–91.
Published: 09 January 2017
... but that it is small and therefore might have remained undetected in former investigations. In the current study, the causal effect estimated from the within–identical twins model—and therefore also in the ACE-beta model—is not statistically distinguishable from zero. Only if we pool identical and fraternal twins...
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Includes: Supplementary data
Journal Article
Demography (2011) 48 (4): 1347–1375.
Published: 13 August 2011
... – 1322 . 10.1093/ije/dyp226 Gaist , D. , Bathum , L. , Skytthe , A. , Jensen , T. K. , McGue , M. , Vaupel , J. W. , & Christensen , K. ( 2000 ). Strength and anthropometric measures in identical and fraternal twins: No evidence of masculinization of females...
Journal Article
Demography (2013) 50 (2): 421–444.
Published: 14 November 2012
... may be mostly fraternal. 16 Identical twins often have perinatal problems (e.g., resulting from sharing the same placenta) that fraternal twins do not have, which often results in lower birth weight in the former. In this study, I focused most of my attention on the preconception environment...
Journal Article
Demography (2020) 57 (2): 559–576.
Published: 08 April 2020
... ) showed that this selection issue is primarily attributable to dizygotic (fraternal) twins. Dizygotic twins become more likely with increasing age of the mother (Fauser et al. 2005 ; Reddy et al. 2005 ) and the use of IVF treatments (Thurin et al. 2004 ), creating a correlation between twin births...
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Includes: Supplementary data
Journal Article
Demography (2010) 47 (1): 145–162.
Published: 01 February 2010
... studies, sibling endowment varies within fraternal twin pairs because they are not genetically identical and remains the same in identical twin pairs because they are genetically identical. 6. One of the limitations of estimating a within-family or mother ¿ xed-effect (MFE) model is that we are un- able...
Journal Article
Demography (2010) 47 (2): 393–414.
Published: 01 May 2010
... of identical twins (= 1.00) and fraternal twins (= 0.50). The value for ambiguous siblings represented the average of half and full siblings.2 In addition, because all related kin in these analyses lived in the same household environ- ments for at least part of their childhood and adolescence, common...
Journal Article
Demography (2009) 46 (4): 695–715.
Published: 01 November 2009
... as an instrument for fertility, wrote that age of menarche is an individual characteristic 10. Sisters are de ned as nontwin full siblings, fraternal twins, identical twins, twins of uncertain zygosity, and half siblings. 11. The variables in the vector Xi include age at Wave I, PPVT score, religiosity, race...
Journal Article
Demography (2020) 57 (6): 2143–2167.
Published: 25 September 2020
... are fraternal (dizygotic) and share 50% of their genetic material (about the same amount of genetic material that nontwin siblings share). Thus, it is plausible that there are unobservable genetic differences between twins that lead to differential parental care and attention, net of child sex. Another...
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Includes: Supplementary data
Journal Article
Demography (1997) 34 (1): 31–48.
Published: 01 February 1997
.... For example, Kallman and Sander (1948, 1949) observed a much smaller difference be- tween the life spans of identical (MZ) than of fraternal (DZ) twins. Wyshak (1978) found that correlation coefficients be- tween the life spans of twins not classified by zygosity were Px = .14 for males and Px = .24...
Journal Article
Demography (2010) 47 (Suppl 1): S111–S130.
Published: 01 March 2010
.... , Bathum L. , & Christiansen L. ( 2007 ). Biological Indicators and Genetic Information in Danish Twin and Oldest-Old Surveys . In M. Weinstein , J.W. Vaupel , & K.W. Wachter (Eds.), Biosocial Surveys (pp. 15 – 41 ). Washington, DC : National Academies Press...
Journal Article
Demography (2012) 49 (4): 1385–1405.
Published: 03 August 2012
.... Griliches ( 1979 ) used adult IQ as a measure of initial endowment to analyze a sample of sibling pairs and found evidence of compensatory investment strategies. Analyzing a sample of adult male twins, Behrman et al. ( 1982 ) showed that concerns regarding how earnings are distributed among children help...
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Journal Article
Demography (2010) 47 (1): 1–22.
Published: 01 February 2010
... plays in health, the Add Health design included the biological domain from the start by embedding a genetic sample of over 3,000 pairs of adolescents with varying degrees of genetic resemblance, including identical and fraternal twins, full siblings, half siblings, cousins, and adolescents growing up...
Journal Article
Demography (2021) 58 (3): 1011–1037.
Published: 01 June 2021
... in socioeconomically advantaged families and reinforcing parental responses in socioeconomically disadvantaged families. Grätz and Torche (2016) , however, found neither reinforcing nor compensatory parental responses to birth weight differences between twins, and they found reinforcing parental responses to twin...
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Includes: Supplementary data