dizygotic twins


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Related to dizygotic twins: fraternal twins, Monozygotic twins

di·zy·got·ic twins

twins derived from two zygotes.

dizygotic twins

two offspring born of the same pregnancy and developed from two ova that were released from the ovary simultaneously and fertilized at the same time. They may be of the same or opposite sex, differ both physically and genetically, and have two separate and distinct placentas and membranes, both amnion and chorion. The frequency of dizygotic twinning varies according to ethnic origin (the highest incidence occurs in African-Americans, the lowest in Asian-Americans, with Caucasians intermediate), maternal age (the highest rate occurs when the mother is 35 to 39 years of age), and heredity (showing an increase in the female genetic line rather than the male, although fathers may transmit the disposition to double ovulation to their daughters). In general the overall ratio is two thirds dizygotic twinning to one third monozygotic. Also called binovular twins, dissimilar twins, false twins, fraternal twins, heterologous twins.
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Development of dizygotic twins

dizygotic twins

Fraternal twins Twins resulting from 2 separate fertilized eggs, liberated simultaneously from the ovaries, which develop in separate or partially fused chorion and placenta, and usually a separate amniotic sac. Cf Monozygotic twins.

di·zy·got·ic twins

(dī-zī-got'ik twinz)
Twins derived from two zygotes.
Synonym(s): fraternal twins, heterologous twins.

dizygotic twins

or

fraternal twins

a pair of children born at the same time to the same mother but each developing from a different fertilized egg. Such twins are therefore nonidentical, being equivalent to normal SIBLINGS, and can be of the same or different sexes. Compare MONOZYGOTIC TWINS.
References in periodicals archive ?
We compared these proportions for the monozygotic and dizygotic twins.
Among the female dizygotic twins of 76 boys with ASD, the probandwise concordance rate was 5.
The lifetime risk of BP in first-degree relatives of a bipolar patient is 40% to 70% for a monozygotic twin, and 5% to 10% for dizygotic twins and all other first-degree relatives (Muller-Oerlinghausen, Berghofer, & Bauer, 2002).
The genetics of psoriasis are complex and the disease is highly heritable as evidenced by an increased rate of concordance in monozygotic twins over dizygotic twins (35%-72% vs.
14) Strong genetic contributions were first detailed in observational studies showing that parents of patients with atopic dermatitis often have a history of the disease and concordance rates are higher for monozygotic twins compared with dizygotic twins.
In dizygotic twins (derived from two separately fertilized eggs), 7.
The results showed no difference in concordance rates for PD in monozygotic and dizygotic twins 60 or more years of age.
Genetic effects on baseline values of C-reactive protein and serum amyloid A protein: a comparison of monozygotic and dizygotic twins.
If a condition has a strong genetic component, then monozygotic twins should be highly concordant for the condition; dizygotic twins should show some level of concordance but not to the same extent as monozygotic twins.
Furthermore, the concordance rate was higher in dizygotic twins than non-twin siblings.
Irritable bowel syndrome (IBS) was reported by 117 pairs of monozygotic twins and 164 pairs of dizygotic twins on questionnaires completed by 6,060 twin pairs living in Virginia.
Mothers share the same number of genes with their children as dizygotic twins share with each other; yet the proportion of dizygotic twins who have IBS and a mother with IBS is significantly greater that the proportion of dizygotic twins with IBS who have a cotwin with IBS.