Characteristics: Monozygotic twins originate from a single fertilized ovum dividing into two embryos, while dizygotic twins result from ovulation of two eggs during a single menstrual cycle.
Incidence: Twins are delivered 1 in 77 Caucasian births; 70 percent are dizygotic and 30 percent are monozygotic.
Cause: Dizygotic twinning is related to increased levels of maternal follicle stimulating hormone.
Clinical Sensitivity: 99 percent.
Methodology: PCR followed by capillary electrophoresis; specimens are analyzed using 15 autosomal short tandem repeat markers (D8S11 79, D21S11, D7S820, CSF1PO, D3S1358, THO1, D13S317, D16S539, D2S1338, D19S433, vWa, TPOX, D18S51, D5S818 and FGA) and one gender marker (Amelogenin).
Analytic Sensitivity: 99 percent.
Limitations: Specificity may be compromised by rare primer site mutations.
See Compliance Statement B: www.aruplab.com/CS
||Results from both twins will be compared; therefore a specimen from each twin must be obtained and genotyped.
||81265; if additional samples, add 81266 for each
||Fetal Zygosity (Twin Zygosity Testing), Mono/Dizygotic Differentiation (Twin Zygosity Testing), Newborn Zygosity (Twin Zygosity Testing), Zygosity, Twin Pre/Postnatal (Twin Zygosity Testing)