While resting myocardial blood flow wasn't different in any of the twin pairs, dizygotic twins
with major depression had a 14% lower coronary flow rate response to adenosine challenge compared to their brothers without depression.
Among the female dizygotic twins of 76 boys with ASD, the probandwise concordance rate was 5.
Our study provides evidence that the rate of concordance in dizygotic twins may have been seriously underestimated in previous studies, and the influence of genetic factors on the susceptibility to develop autism overestimated.
, in contrast, show a 0 to 10% concordance under the same models (Folstein & Rutter, 1977; Folstein & Rosen-Sheidley, 2001).
Twin studies are conducted with equal numbers of both monozygotic and dizygotic twins.
65) In perhaps the most comprehensive study, Reznikoff, Domino, Bridges, and Honeyman studied 117 pairs of monozygotic and dizygotic twins found through the Connecticut Twin Registry, which maintains a list of all multiple births in Connecticut since 1897.
The method also allows the determination of contributions to the circulating fetal DNA by individual fetuses of dizygotic twins.
Dizygotic twins would be suspected when the relative concentrations of the fetal alleles are shown to vary widely among SNP sites.
This rate is approximately 4% among dizygotic twins
This study was also one of the first to be able to accurately calculate RRR, by including twice as many cases of ASD and more detailed family data, including monozygotic and dizygotic twins
and cousins, than previous studies.
Genetic analysis thus demonstrated that the embryos were dizygotic twins
, although the origins (i.
Dizygotic twins are no more alike genetically than regular siblings, on average sharing 50 percent of their genes.
For the new study, the researchers recruited 78 monozygotic-twin pairs and 27 pairs of dizygotic twins from the registry.
Of these, 346 were monozygotic and 318 were dizygotic twins
A well-conducted study involving 4,402 Vietnam War-era mono- and dizygotic twins
has shed light on the longstanding genes vs.