There have been only five reported cases of concordant DS in dizygotic
twins with confirmed chromosomal analyses [2, 6, 13].
Meda War, "The use of skin grafting to distinguish between monozygotic and dizygotic
twin in cattle," Heredity, vol.
Novel variants in growth differentiation factor 9 in mothers of dizygotic
Median, Confidence Interval (CI), Intrapair Variance of Displacement Speed (VDS) and Partial Correlations Controlling for Age (r), Height, Body Mass, Displacement Speed (DS) and the Heritability of: (a) Monozygotic and Dizygotic
Twins of Both Sexes; (b) Female Monozygotic and Dizygotic
Twins; and (c) and Male Monozygotic and Dizygotic
For the new study, the researchers recruited 78 monozygotic-twin pairs and 27 pairs of dizygotic
twins from the registry.
This assay allows the genotyping of 15 multiple informative genetic markers (CSF1PO, D2S1338, D3S1358, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11, D5S51, FGA, TH01, TPOX, VWF, and AMELXloci), which allows for the identification of monozygotic and dizygotic
Also, those women undergoing in vitro fertilisation and other fertility treatments have a higher risk of having twins, that are dizygotic
, monozygotic or identical, or other multiples.
It is more commonly seen in monozygotic twins as compared to dizygotic
twins and singletons, the reported incidence being 100-150 times higher.
In addition, the reported 63% concordance rate among monozygotic twins compared to the null concordance among dizygotic
pairs , scoring as the highest among autoimmune diseases , indicated that gene susceptibility played an important role in the pathogenesis of PBC.
We note how de novo mutations may also help explain why the concordance rate for autism is so markedly higher in monozygotic than dizygotic
(1) In addition to being matched on typical characteristics such as age or race, twins are by design matched in varying degrees on genetic propensity: monozygotic (MZ) twins share 100% of their genetic makeup and dizygotic
(DZ) twins share on average 50%.
The studies conducted by McGuffin and Reich on monozygotic and dizygotic
twins suggest genetic predisposition because high concordance rate was found in monozygotic with absence in dizygotics
and more prevalence in first degree relatives of OCD than in population at large.